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301 - LTM Specialist - Dump Information
| Vendor | : | F5-Networks |
| Exam Code | : | 301 |
| Exam Name | : | LTM Specialist |
| Questions and Answers | : | 49 Q & A |
| Updated On | : | November 8, 2017 |
| PDF Download Mirror | : | 301 Brain Dump |
| Get Full Version | : | Pass4sure 301 Full Version |
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301 | F50-531 | F50-526 | F50-506 | 001-ARXConfig | F50-536 | F50-529 | F50-515 | 301b | F50-521 | 101 | F50-528 | F50-533 | 201 | F50-532 | 771-101 | F50-513 | F50-522 | 106 |Latest Exams added on bigdiscountsales
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QUESTION: 47
A
BIG-IP has two SNATs, a pool of DNS servers and a virtual server
configured to load-balance UDP traffic to the DNS servers. One SNAT's
address is 64.100.130.10; this SNAT is defined for all
addresses. The second SNAT's address is 64.100.130.20; this
SNAT is defined for three specific addresses, 172.16.3.54,
172.16.3.55, and 172.16.3.56. The virtual server's
destination is 64.100.130.30:53. The SNATs and virtual server have
default VLAN associations. If a client with IP address 172.16.3.55
initiates a request to the virtual server, what is the source IP address
of the packet as it reaches the chosen DNS server?
A. 64.100.130.30
B. 172.16.3.55
C. 64.100.130.20
D. 64.100.130.10
Answer: C
QUESTION: 48
A, steaming profile will do which of the following?
- Search and replace all occurrences of a specified string only is responses processed by a virtual server.
- Search and replace all occurrences of a specified string only in request processed by a virtual server.
- Search and replace all occurrences of a specified string in requests and responses processed by a virtual server.
- Search and replace the first occurrence of a specified of a specified string in either a request or response processed by a virtual server.
Answer: C
QUESTION: 49
A
monitor has been defined using the HTTP monitor template. The send and
receive strings were customized, but all other settings were left at
their defaults. Which resources can the monitor be assigned to?
- only specific pool members
- most virtual severs
- most nodes
D. most pools
Answer: D
F5-Networks 301 Exam (LTM Specialist) Detailed Information
302 - BIG-IP Global Traffic Manager (GTM) Specialist ExamExam Summary:
Successful completion of the 302-GTM Technology Specialist exam indicates that the candidate possesses the knowledge and understands the concepts and technology standards that are applicable to application delivery architects and application delivery engineers working with F5 BIG-IP GTM.
Minimally Qualified Candidate for the 302 Exam:
The MQC for GTM Specialist is able to understand the basic operation of DNS protocol, deploy and test configurations, troubleshoot and remedy common misconfigurations. The MQC is able to explain the capabilities of DNS services to deploy applications globally.
The MQC Can Do the Following and More Without Assistance:
Explain the DNS query process.
Recognize when to use ZoneRunner to manage DNS records on GTM.
Configure and troubleshoot the operational aspects of DNS.
Perform basic architecture for deployments.
For additional exam prep, download this candidate-produced study guide.
F5 Certified BIG-IP Administrator
(F5-CA)
F5-CA Requirements
Exam 101 - Application Delivery Fundamentals
Exam 201 - TMOS Administration
F5 Certified Technology Specialists
(F5-CTS)
F5-CTS LTM Requirements
– F5-CA Certification
Exam 301a - LTM Specialist: Architect, Setup, and Deploy
Exam 301b - LTM Specialist: Maintain and Troubleshoot
F5-CTS GTM Requirements
– F5-CA Certification
Exam 302 - GTM Specialist
F5-CTS ASM Requirements
– F5-CA Certification
Exam 303 - ASM Specialist
F5-CTS APM Requirements
– F5-CA Certification
Exam 304 - APM Specialist
F5 Certified Solution Expert
(F5-CSE)
F5-CSE Security Requirements
– F5-CA Certification
– F5-CTS LTM Certification
– F5-CTS GTM Certification
– F5-CTS ASM Certification
– F5-CTS APM Certification
Exam 401 – Security Solution Expert
304 - BIG-IP Access Policy Manager (APM) Specialist Exam
Exam Summary:
The 304-APM Technology Specialist exam is the required to achieve Certified F5 Technology Specialist, APM status. Successful completion of the APM Technology Specialist exam acknowledges the skills and understanding necessary for day-to-day management of Application Delivery Networks (ADNs) that incorporate technologies based on the F5 TMOS operating system (v11).
Minimally Qualified Candidate for the 304 Exam:
The minimally qualified candidate (MQC) understand how APM interacts with the industry remote access, authentication, and authorization standards—and can independently install, configure, implement, troubleshoot (advanced), maintain, and upgrade APM in various application environments.
The MQC Can Do the Following Without Assistance:
Configure access policies; the less-than-MQC can only review or amend them.
Apply SSL/VPN client and server side, including certs; the less-than-MQC has no experience with SSL/VPN.
Configure APM to enable SSO; the less-than-MQC may only be aware of its existence.
Configure and troubleshoot endpoint security; the less-than-MQC can only perform basic/limited troubleshooting.
401 - F5 Certified Security Solution Expert Exam
Exam Summary:
Successful completion of the 401-Security Solution Expert exam acknowledges the skills and understanding to discover business requirements regarding security and articulate technical requirements driven by the business. Candidates can also apply F5 solutions to meet technical requirements for a security solution and articulate the value of the solution (v12).
Summary Description of the MQC:
The F5-CSE, Security minimally qualified candidate will have experience designing security solutions leveraging LTM, GTM, ASM, APM, AFM, BIG-IQ modules, IP Intelligence (IPI), WebSafe, and MobileSafe. The MQC can analyze technical requirements, translate them into security requirements, apply and modify security architectures utilizing F5 technology to meet the requirements, and articulate the value of the solution
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Other Hedge Funds, luding , Fisher Asset Management boosted its stake in FFIV in the latest quarter, The investment management firm added ">301 additional shares and now holds a total of 7,986 shares of F5 Networks which is valued at $984,115.Chevy Chase Trust Holdings reduced its stake in FFIV by selling 1,971 shares or 3.44% in the most recent quarter. The Hedge Fund company now holds 55,247 shares of FFIV which is valued at $6,933,499. F5 Networks makes up approx 0.04% of Chevy Chase Trust Holdings’s portfolio.Bnp Paribas Arbitrage Sa boosted its stake in FFIV in the latest quarter, The investment management firm added 12,201 additional shares and now holds a total of 32,152 shares of F5 Networks which is valued at $4,035,076. F5 Networks makes up approx 0.02% of Bnp Paribas Arbitrage Sa’s portfolio.Independent Portfolio Consultants boosted its stake in FFIV in the latest quarter, The investment management firm added 190 additional shares and now holds a total of 5,774 shares of F5 Networks which is valued at $724,637. F5 Networks makes up approx 0.23% of Independent Portfolio Consultants’s portfolio.Washington Trust Bank boosted its stake in FFIV in the latest quarter, The investment management firm added 6 additional shares and now holds a total of 14,206 shares of F5 Networks which is valued at $1,782,853. F5 Networks makes up approx 0.43% of Washington Trust Bank’s portfolio.
F5 Networks closed down -1.42 points or -1.15% at $121.81 with 8,74,094 shares getting traded on Tuesday. Post opening the session at $123.22, the shares hit an intraday low of $121.22 and an intraday high of $123.3 and the price fluctuated in this range throughout the day.Shares ended Tuesday session in Red.
On the company’s financial health, F5 Networks reported $1.81 EPS for the quarter, beating the analyst consensus estimate by $ 0.02 according to the earnings call on Jul 20, 2016. Analyst had a consensus of $1.79. The company had revenue of $496.52 million for the quarter, compared to analysts expectations of $495.70 million. The company’s revenue was up 2.7% compared to the same quarter last year. During the same quarter in the previous year, the company posted $1.67 EPS.
Many Wall Street Analysts have commented on F5 Networks. Company shares were Initiated by Wunderlich on Jul 21, 2016 to “Buy”, Firm has raised the Price Target to $ 110 from a previous price target of $100 .F5 Networks was Downgraded by Credit Suisse to ” Neutral” on Jul 21, 2016. Company shares were Reiterated by RBC Capital Mkts on Jul 21, 2016 to “Sector Perform”, Firm has raised the Price Target to $ 120 from a previous price target of $115 .
F5 Networks . is the developer and provider of application delivery services. The Company’s core technology is a full-proxy programmable software platform called TMOS (Traffic Management Operating System). It helps organizations seamlessly scale cloud data center and software-defined networking deployments to successfully deliver applications to anyone anywhere at any time. It works with many technology companies to improve manageability strengthen security and ensure faster and more successful deployments. Its applications include availability and delivery. It can remove the roadblocks in one’s network to efficiently and securely deliver applications that are available to users when and where they need them. It can also accelerate one’s application response time minimize latency and delays and reduce the number of data round trips necessary to complete a web request.
Article by ArticleForge
Networks, . (NASDAQ: FFIV), the global leader in Application
Delivery Networking, today announced that company management will
participate in the Morgan Keegan’s 2009 "Summer in the City" Technology
Conference in New York on August 11, the Oppenheimer’s Annual
Communications & Technology Conference in Boston on August 12, and the
Canaccord Adams' 29th annual Global Growth Conference in Boston on
August 13.
F5’s presentation schedule is as follows:
The Morgan Keegan presentation will begin at 1:00 p.m. ET on Tuesday,
August 11 at the Waldorf-Astoria Hotel (">301 Park Avenue, New York).
The Oppenheimer presentation will begin at 11:10 a.m. ET on Wednesday,
August 12 at the Four Seasons Hotel (200 Boylston Street, Boston).
The Canaccord Adams presentation will begin at 9:30 a.m. ET on
Thursday, August 13 at the InterContinental Hotel (510 Atlantic
Avenue, Boston).
F5 representatives for the three conferences include John McAdam,
President and Chief Executive Officer, and Andy Reinland, SVP and Chief
Finance Officer.
Interested viewers can go to .f5maboutinvestor-relationsevents-calendar.html
to access a direct link to the webcasts for the presentations. Webcasts
will be accessible through September 14, 2009.
About F5 Networks
F5 Networks is a global leader in Application Delivery Networking (ADN),
focused on ensuring the secure, reliable, and fast delivery of
applications. F5’s flexible architectural framework enables
community-driven innovation that helps organizations enhance IT agility
and dynamically deliver services that generate true business value. F5’s
vision of unified application and data delivery offers customers an
unprecedented level of choice in how they deploy ADN solutions. It
redefines the management of application, server, storage, and network
resources, streamlining application delivery and reducing costs. Global
enterprise organizations, service and cloud providers, and Web 2.0
content providers worldwide trust F5 to keep their business moving
forward. For more information, go to .f5m.
F5 Investor Relations
John Eldridge, 206-272-6571
j.eldridgef5m
Article by ArticleForge
In today's highly competitive e-business world, companies must deliver Web content faster than their competitors to attract and retain Internet customers. According to a study that Jupiter Research Center conducted in 2000, 7 percent of customers will abandon a Web page if the download time is less than 7 seconds, 30 percent will move on if the download time is 8 to 11 seconds, and 70 percent will leave the Web page if the download time is 12 seconds or longer.
To avoid losing customers because of slow download times and to improve customers’ Web surfing experience, many companies deploy load balancers to equalize the load among multiple Web servers in one site or across two or more sites. (For more information about load balancers, see "Web Server Load Balancers," April 2000.) Some companies place reverse proxy servers in front of Web servers to cache Web pages that external customers frequently access, and many companies use cache servers in their intranets to cache Web pages that their internal users frequently access. (For more information about Web caching, see "Surfing Web-Caching Technology, Part 1," September 1999, and "Surfing Web-Caching Technology, Part 2," October 1999.) Load balancers efficiently select the least-busy Web server among several mirrored servers to speed Web content retrieval. However, a load balancer doesn’t minimize the number of hops that content must make to reach a requesting user; the average number of hops between a browser or browser's cache server and a Web site is 17. So, many hops can degrade a company’s Internet-content delivery performance, even if the company’s Web site quickly retrieves the content and the customer has a fast Internet link. Even with a cache server, the hit ratio will be only about 40 percent. The other 60 percent of requests must travel to the originating Web server over the Internet.
To provide better quality and faster Web service, content providers want to put their content as close as possible to the customers who want it. Over the past 2 years, this concept has evolved into a new Web architecture and Internet service called Content Delivery Network or Content Distribution Network (CDN). The Internet Engineering Task Force (IETF) calls this new architecture a Content Network (CN).
A CDN is a smart, application-layer network that a CDN service provider builds on the Internet to guarantee high-performance content delivery. Organizations such as content providers and Web-hosting services can subscribe to CDN services—many organizations are already taking advantage of CDN’s benefits. The High Tech Resource Consulting Group, a market research firm, estimates that the CDN market will grow to $2.3 billion by 2002.
CDN Architecture and ServicesA CDN replicates a Web server’s content from the origin server (CDN terminology for the originating Web server) to the CDN's surrogates (i.e., content or cache servers) at various Points of Presence (POPs) near customers. A CDN POP often has multiple surrogates and uses a load balancer to spread the load among them.
When a customer requests content, the CDN directs the user's request to the nearest POP, whose load balancer forwards the request to the least-loaded surrogate. This surrogate retrieves the content from its cache and delivers the content through the load balancer to the customer. Figure 1 shows CDN architecture and the three major CDN functions: accounting, content distribution, and request routing.
AccountingAs Figure 1 shows, accounting takes place on the surrogate level. Each surrogate logs content usage, such as the speed (in megabits per second) with which the surrogate delivers content and the number of hits that particular content (i.e., a specific page or object) receives, and reports the usage information to a central accounting system. The CDN uses the gathered accounting information to charge subscribers, produce statistics for subscribers, and analyze the workload of surrogates and POPs.
Content DistributionA CDN can use two methods to distribute content from an origin server to surrogates: the Internet or satellite broadcast. Using the Internet to replicate content is the simple and natural choice. Distribution occurs when a company changes content on its origin Web server or when the CDN adds a new surrogate to the network. Because only one distribution takes place from the origin server to each surrogate per content change, the bandwidth consumption and workload for content distribution is almost nothing when compared with the number of content accesses and fetches each surrogate performs for requesting customers. Many CDN service providers, such as Akamai Technologies, Digital Island, and Mirror Image Internet, use the Internet for content distribution.
If a company’s origin server is far away from surrogate locations or slow links exist between the origin server and the surrogates, content distribution performance for rich content such as realtime streaming multimedia will be unpredictable. For such content, satellite broadcasting provides a high-performance transmission path from the origin server to remote surrogate locations. However, satellite broadcasting is an expensive solution. Using a satellite channel can cost hundreds of thousands of dollars per month. Despite this cost, several CDN service providers, such as Cidera and Loral CyberStar, use satellite broadcasting.
A CDN uses either the push or pull method to maintain up-to-date replicated content on its surrogates. In the push method, a content distribution controller monitors content on the origin server. When a change occurs, the controller copies and synchronizes the change from the origin server to remote surrogates. Consequently, the surrogates always contain up-to-date content. Several CDN service providers, such as Mirror Image Internet, use the content push method.
A content distribution controller can be a hardware appliance (e.g., F5 Networks' GLOBAL-SITE Controller) or a software package (e.g., Inktomi's Content Delivery Suite) that can run on a dedicated server or on the origin server. With either the hardware or software content-distribution solution, you can specify which files, pages, objects, and applications on the origin server you want the controller to replicate, to which surrogates, and under what conditions. A content distribution controller can publish content to popular Web server software-based servers, such as Apache, Microsoft IIS, and Netscape Enterprise Server. However, controllers often require that surrogates run the associated surrogate product from the controller’s vendor. For example, F5 Networks' GLOBAL-SITE Controller works with F5 Networks' EDGE-FX Cache, and Inktomi's Content Delivery Suite works with Inktomi's Traffic Server. Some vendors have been working together to improve CDN product interoperability. In April 2001, F5 Networks and Inktomi announced a strategic alliance to integrate their CDN products.
In contrast to CDNs that use the push method, CDNs that use the content pull method don't have a dedicated content distribution controller to push the changed content to surrogates. When a CDN’s request-routing system directs a customer's request to a specific surrogate, the surrogate retrieves the locally cached content and passes it to the user. If the content isn’t cached locally on the surrogate, the surrogate fetches the requested content from the origin Web server.
Surrogates that use the pull method work like ordinary cache servers. The surrogates update cached content by checking for content changes on the origin server, and they purge cached content that users haven’t requested in a long time. Most CDN product manufacturers offer a cache server-based surrogate in their product lines (e.g., CacheFlow's Edge Accelerator and Server Accelerator, Network Appliance's NetCache, F5 Networks’ EDGE-FX Cache, Inktomi's Traffic Server). Most CDN service providers use the content pull method.
Although the pull method doesn’t provide as high a content hit ratio as the push method does, the hit ratio can still approach 100 percent, and a pull-method CDN will be much faster than a typical cache system. If a surrogate’s average hit ratio is 99 percent and we assume that content delivery time is 0.1 second for a hit and 8 seconds for a miss, then the average content delivery time for a CDN surrogate is 0.179 seconds. If the average hit ratio on a typical non-CDN cache server is 40 percent and we assume the same content delivery times that we assume for the CDN surrogate, then the average content delivery time for a non-CDN cache server is 4.84 seconds. Therefore, a pull-method CDN delivers content about 27 times as fast as a typical cache system.
Request RoutingAnother important CDN service is request routing (aka content redirection and content routing), which directs users’ requests to an appropriate surrogate. A CDN request-routing system selects a surrogate according to various criteria, such as proximity of the surrogate network to the user, surrogate load, and content availability. The IETF recently studied CDNs’ request-routing techniques and concluded that CDNs use three primary request-routing mechanisms: DNS, transport-layer, and application-layer request routing. (To read the IETF report, click here.) CDNs can implement a combination of all three types.
DNS request routing. When a client requests content from a Web site, the client first needs to resolve the content server’s IP address through DNS. A local DNS server answers the client's query by returning an A record for the site. This A record contains the IP addresses for one or more selected surrogates. If the client receives more than one IP address, the client chooses a surrogate in a round-robin fashion. If a CDN uses a load balancer in the POP, the IP address in the A record is a virtual IP (VIP) address. CDNs often use smart servers, which have more capabilities than a BIND or Microsoft DNS server and direct users’ requests to the most appropriate surrogate.
Suppose examplem, a CDN subscriber, has delegated the subdomain .examplem from its authoritative DNS server to the CDN's smart DNS server so that the smart DNS server can control surrogate selection for .examplem. Figure 2 illustrates the following steps in smart DNS request routing:
A user needs to access .examplem. The user’s local DNS server looks up the IP address of .examplem.
If the local DNS server doesn't have a cached address for
.examplem, the server asks examplem’s authoritative DNS server for the
IP address of .examplem. The authoritative DNS server replies to the
local DNS server with the Name Server (NS) record of .examplem. This
record provides the name of the CDN’s request-routing DNS server for
.examplem.
The local DNS server sends the name-resolution request to the CDN request-routing DNS server.
The request-routing DNS server instructs the load balancer in
each CDN POP to determine the network proximity from the POP to the
user's local DNS server. The request-routing DNS server uses this
information to determine which POP is most appropriate for the user.
(You should always disallow recursive resolution on an authoritative
server to prevent the server from resolving IP addresses for the local
DNS server. If you don’t, CDN load balancers will measure the POP’s
proximity to the authoritative DNS server rather than to the local DNS
server.)
The load balancer in each POP probes the local DNS server to
measure the load balancer’s network proximity to the user’s local DNS
server. The request-routing DNS server can also perform this measurement
task if it’s in a POP. This measurement task typically requires that
the POP’s load balancer and the POP’s request-routing DNS server be from
the same vendor.
Load balancers report the results of the network-proximity
measurement to the request-routing DNS server. The load balancers also
report their POP workload and surrogate availability status.
The request-routing DNS server uses the metrics it receives
from the load balancers to determine the best POP surrogate for the user
and sends the VIP address of the chosen surrogate to the user's local
DNS server. To prevent the local DNS server from caching the address for
long, the VIP address’s Time to Live (TTL) value is usually very short.
If the local DNS server caches the address for too long, availability
problems might arise if the POP surrogate becomes unavailable.
The local DNS server passes the VIP address to the user.
The user requests content from the chosen POP surrogate.
Transport-layer request routing. As I mentioned, DNS request routing
uses the IP address of a user's local DNS server as a factor in
selecting a surrogate for the user. If the user's DNS server isn’t close
to the user, the DNS server address can introduce misleading
information in the DNS request-routing system’s surrogate selection.
Transport-layer request routing solves this problem.
After the DNS request-routing system chooses a surrogate for a user's initial connection and directs the user to the surrogate, a transport-layer request-routing system examines the first packet of the user request to determine whether the chosen surrogate is optimal for the user. Each POP includes a transport-layer request-routing system that vendors usually implement in the load balancer. Based on the information in the first packet, including the IP address, port number, transport-layer protocol, and user policy and performance metrics, the transport-layer request-routing system determines whether it needs to select a more suitable surrogate POP for the user request.
Figure 3 illustrates triangulation, a common implementation of transport-layer request routing. After a user receives a VIP for a surrogate in the CDN’s POP1, the user sends a content request to the surrogate. POP1's transport-layer request-routing system uses the information in the user’s first packet to determine that POP2 can better fulfill the user's request (e.g., POP2 might provide the user better ftp download capabilities). POP1 then forwards the request to POP2's transport-layer request-routing system. POP2 recognizes that the arriving request is from POP1's transport-layer request-routing system. After POP2 fetches the requested content, POP2's transport-layer request-routing system changes the source IP address in the content packet’s IP header to POP1's VIP address and sends the packet to the user. When the user receives the packet, the user thinks the packet is from POP1. The user continues sending requests to POP1 until the session finishes. Triangulation redirection works well because upstream traffic from users is light compared with downstream traffic from a POP. Using triangulation to provide a more efficient downstream path for user requests improves content-delivery performance.
Application-layer request routing. An application-layer request-routing system conducts a deeper inspection of the user request by checking the application information beyond the transport layer in the received packet. This examination lets the application-layer request-routing system determine the best surrogate for a user request based on information at the individual-object level. For example, when a user requests a news page that contains news items, graphics, and advertisements, the application-layer request-routing system can redirect the user to retrieve each object from the best surrogate. Three major methods for implementing application-layer request-routing systems exist: header inspection, HTTP and Real Time Streaming Protocol (RTSP) redirection, and content modification.
In the header of a session request, HTTP, RTSP, and Secure Sockets Layer (SSL) applications provide useful information, such as a URL, cookie, session identifier, site specification, or language specification. For example, an SSL session requires a persistent connection between a user and the surrogate running the SSL application. By inspecting the user information in the user’s cookie or the surrogate information in the SSL session identifier, an application-layer request-routing system can direct the user’s requests to the same surrogate for the entire session.
Alternatively, an application-layer request-routing system can use HTTP and RTSP redirection to redirect a user’s GET request to another surrogate. If a user requests information from a surrogate that’s overloaded or down, the application-layer request-routing system responds to the user’s GET request with a ">301 (moved temporarily) or 302 (moved permanently) code message that includes the IP address of the surrogate with which the user was communicating. The user’s browser can then initiate a new session.
The third method, content modification, lets a content provider control request-routing decisions. When the content provider subscribes to a CDN service, the content provider rewrites URLs on the origin server. For example, an HTML Web page often contains plaintext as well as embedded objects such as graphics and images. The Web page uses embedded HTML directives in the form of URLs to reference the embedded objects. Usually, the embedded URLs point to the embedded objects on the same origin server that contains the Web page. However, to take advantage of a CDN service, the content provider can change the embedded URLs to CDN URLs so that the CDN service can deliver bandwidth-sensitive objects such as graphics, images, and streaming multimedia.
As Figure 4 shows, when a user requests a Web page, the request goes to the origin server first. The origin server returns to the user the HTML Web page with the embedded CDN URLs. The user then retrieves the embedded objects from the CDN. The user must resolve the domain name in a CDN URL so that the CDN can use DNS request routing to select an optimal POP and surrogate to fulfill the user request. The CDN then uses transport- and application-layer request routing to redirect the user’s request to the best POP or surrogate.
When content changes on the origin server, the content provider can use a software utility to manually or automatically rewrite embedded URLs on the origin server. An example of application-layer request routing that uses content modification is Akamai's FreeFlow content delivery service. Akamai’s FreeFlow Akamaizer software tool can automate URL modification.
CDN PeeringA CDN can quickly deliver content to users close to the CDN’s surrogates. However, no CDN can cover all the networks across the Internet. Thus, to offer fast content delivery to geographically disparate users, a content provider must subscribe to multiple CDN services.
To expand their services globally over more networks, CDNs need to link together and deliver content for each other’s customers as well as for their own. This implementation is called CDN peering or content peering.
Content delivery across multiple CDNs isn’t simple. When a user requests content that requires the involvement of two or more CDNs, the CDNs’ request-routing systems must work together to determine the best CDN for the user request. In August 2000, several vendors formed two industry alliances—Content Alliance and Content Bridge—to help develop CDN peering. To develop content peering architecture and standards, IETF formed the Content Distribution Internetworking Group in December 2000. The group includes members from both alliances and has published several drafts about content peering architecture and standards. In January 2001, Content Bridge began delivering its content peering service, in which a content provider can access the services of any Content Bridge member by subscribing to CDN service from one vendor in the alliance.
CDN services that have a content peering agreement must share core CDN services, including content distribution and request routing. To do so, CDNs use a Content Peering Gateway (CPG) service to link services to one another. The CPG provides the peering functionality. Figure 5 shows an example CDN peering architecture that involves three CDNs.
Through content distribution peering, a CDN can redistribute the content from a content provider’s origin server to other CDNs’ CPGs. In turn, these CPGs pass the content to the necessary surrogates. To distribute content, peering CDNs can use either the push or pull method. For multiple CDNs to be able to deliver content, the peering CDNs’ request-routing systems must work together to serve the content’s namespace. For this setup to work, a content provider must delegate authority for its content URLs to an authoritative request-routing system on the CPG of the CDN to which the content provider subscribes. This authoritative request-routing system further delegates authority to the request-routing systems of all peering CDNs. For DNS request routing, the content provider delegates a subdomain to the authoritative request-routing DNS server, which in turn delegates the subdomain to the request-routing DNS servers of peering CDNs.
When a CDN’s authoritative request-routing system receives a user request, it negotiates with all peering CDN CPGs to determine which CDN should serve the request. The request-routing system then directs the user request to that CDN. The selected CDN uses its internal request-routing mechanism, which is transparent to the authoritative request-routing system and other CDNs, to determine which surrogate should deliver the content to the user. The selected surrogate then delivers the requested content to the user. At the same time, the surrogate reports the accounting information for the delivered content to the accounting system of the surrogate’s CDN. One CDN can request accounting information from or send it to another CDN through the CPG accounting peering function. A billing organization, such as a third-party clearinghouse firm, handles the charge and payment process of content delivery among peering CDNs.
Content Meets Express DeliveryCDN technology is brand new. However, the number of organizations that use CDNs is growing quickly. During an online CDN seminar in March 2001, Content Bridge conducted a survey about which techniques organizations had used to improve content delivery performance. The survey results showed that 25 percent of seminar participants had used CDNs, 15.6 percent had deployed cache servers, 34.4 percent had used mirrored servers, and the remaining 25 percent had tried all three methods.
CDNs are still mainly proprietary services. However, industry alliances and IETF are developing CDN peering architecture and standards that will eventually evolve into a public network in which multivendor products and services use Internet CDN standards to interoperate. Are you ready for your Web content to meet express Internet delivery services?
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Cisco recently provided a grim outlook that was far short of analyst estimates. However, its rivals Juniper, F5, and Polycom reported strong results and provided outlooks close to analyst estimates. They are trading close to 52-week highs, while Cisco is close to its 52-week low. Let’s take a closer look.
Juniper’s FinancialsJuniper reported third quarter revenue of $1.012 billion, up 23% but missing analyst estimates of $1.03 billion. Net income was $134.5 million, or $0.25 per share, versus $83.78 million or $0.16 per share last year. The company ended the quarter with nearly $2.7 billion in total cash and investments and repurchased shares for $135 million.
For the fourth quarter, Juniper expects revenue of $1.12 billion, plus or minus $20 million and non-GAAP EPS of $0.35 to $0.37. Analysts expect EPS of $0.35 on revenue of $1.1 billion. The stock is trading around $34.35 with market cap of about $18 billion. It hit a 52-week high of $36.00 on November 12 and a 52-week low of $23.03 on June 29.
Recent Acquisitions By JuniperLast week, Juniper announced its plans to buy Trapeze Networks for $152 million and the intellectual property assets of Internet video storage and delivery technology company Blackwave for an undisclosed sum. Trapeze Networks is a technology leader in enterprise wireless local area network (WLAN) systems and management software. A recent report by Dell’Oro Group estimates that the enterprise WLAN technology market will grow from $2.2 billion in 2010 to $3.4 billion in 2014. The acquisition will make WLAN infrastructure a key part of Juniper’s portfolio, accelerating the company’s growth in the enterprise market and advancing its vision for the new network. This vision is centered on two significant market trends, mobile Internet and cloud computing. Security is also a critical element of the mobile Internet. Earlier in the quarter, Juniper acquired SMobile Systems, ., a privately held software company focused solely on smartphone and tablet security solutions for the enterprise, service provider, and consumer markets, for $69 million.
Polycom’s FinancialsPolycom (NASDAQ:PLCM), with annual revenue of $967 million, reported third quarter revenue of $308 million, up 27%. Net income was $17 million or $0.20 per share compared to $14 million or $0.16 per share last year. Non-GAAP EPS was $0.38 versus analyst estimates of $0.36 on revenue of $">301 million. Gross margin increased more than one point sequentially and more than two points year-over-year driven by network systems growth. Polycom ended the quarter with $500 million in cash and investments and no debt.
For the fourth quarter, Polycom expects revenue to grow 5% to 7% sequentially or $323.5 million to $329.5 million, beating analyst estimates of $317 million.
Polycom faces stiff competition from Cisco, which recently acquired its rival Tandberg, which held about 31% share in 2009. Cisco recently launched a home video conferencing product, ?mi, priced at $599 to expand its consumer presence. In response to this, Polycom has announced its plans to release videoconferencing applications for Samsung’s Galaxy platform, which powers its Galaxy S smartphone and Galaxy Tab tablet. Sayantani Ghosh of Reuters reports that
“Polycom has similar apps lined up for BlackBerry, Windows Mobile 7, Apple and other Android-based devices, and is hoping to launch these through 2011. Polycom is also talking to consumer-electronics makers to add low-latency video to home devices and is working with “at least one major carrier on a home telepresence system.”
Polycom is trading around $36.76, a three-year high, with market cap of about $3.14 billion.
There has been much M&A activity in the video conferencing sector over the last year. Apart from Cisco’s $3.3 billion Tandberg acquisition, there is LifeSize, which holds about 5.6% of the market. Polycom, the market leader with 35% share, is an attractive acquisition prospect for either HP or Juniper, which are looking to expand their presence in this active sector. The videoconferencing market grew over 5% in 2009 to about $1.7 billion, and Gartner expects the market to reach $8.6 billion by 2013.
F5’s FinancialsUnlike in the video conferencing industry, F5 (NASDAQ:FFIV) doesn’t face much competitive pressure from Cisco, whose focus lies elsewhere, leaving F5 to continue dominating this area. Cloud computing, virtualization, and mobile applications are some of the trends that are driving F5’s growth. F5 reported fourth quarter revenue of $254.3 million, up 45.2% and beating estimates of $248 million. Net income was $48.2 million or $0.59 per diluted share compared to $28.4 million or $0.36 per diluted share last year. F5 ended the year with $862 million in cash and investments after repurchasing $75 million of common stock. Its board of directors also approved a new program to repurchase up to $200 million of the company’s outstanding common stock.
For fiscal year 2010, revenue was $882.0 million, up 35% from $653.1 million in fiscal year 2009. Net income for the year was $151.2 million ($1.86 per diluted share) versus $91.5 million ($1.14 per diluted share) in fiscal year 2009.
For the first quarter, F5 expects revenue of $265 million to $270 million with a GAAP earnings target of $0.62 to $0.64 per diluted share. Analysts expect earnings of $0.73 a share on revenue of $259.8 million. The stock is trading around $132 with market cap of about $10 billion. It hit a 52-week high of $133.70 on November 24.
F5 Gains ADC Market Share at Cisco’s CostAccording to market research firm Infonetics Research, the application delivery controller (ADC) market is back on a growth track after a tumultuous 2009, with worldwide sales up 28% compared to the first quarter of last year.
Saqib Iqbal Ahmed of Reuters reports that
F5 Networks, which had received a takeover overture last year, remains a potential target for technology giants, including IBM, Dell, HP, Oracle, Juniper and Cisco. F5 leads the ADC market and has an almost 20-point lead over Cisco. It gained 8% market share in the recent quarter, half of which came from Cisco.
Cisco’s poor outlook this quarter led to concerns that it was losing its focus in its core routing and switching business while trying to expand in its 30 adjacent markets. However, Jim Duffy of Network World reports that
“Cisco maintained its 72% share of the overall Ethernet switch market and even upped that by 2% from last year. HP and Juniper also gained share sequentially and over the year. HP now stands at 10.5%, from 6.5% a year ago (thanks, 3Com); and Juniper is now just under 2% from 1.3% last year. Share losers during the quarter, both on a sequential and year-over-year basis, were Brocade, Extreme, Avaya, Alcatel-Lucent and Huawei, according to UBS. HP and Juniper share gains seem to be coming from this group rather than from Cisco.”
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issuu company logoHarding Loevner Lp Lowers stake in F5 Networks (FFIV)
F5 Networks (FFIV) : Harding Loevner Lp reduced its stake in F5 Networks by 0.38% during the most recent quarter end. The investment management company now holds a total of 1,863,242 shares of F5 Networks which is valued at $229,607,312 after selling 7,161 shares in F5 Networks , the firm said in a disclosure report filed with the SEC on Oct 11, 2016.F5 Networks makes up approximately 1.63% of Harding Loevner Lp’s portfolio.Other Hedge Funds, luding , Fisher Asset Management boosted its stake in FFIV in the latest quarter, The investment management firm added ">301 additional shares and now holds a total of 7,986 shares of F5 Networks which is valued at $984,115.Chevy Chase Trust Holdings reduced its stake in FFIV by selling 1,971 shares or 3.44% in the most recent quarter. The Hedge Fund company now holds 55,247 shares of FFIV which is valued at $6,933,499. F5 Networks makes up approx 0.04% of Chevy Chase Trust Holdings’s portfolio.Bnp Paribas Arbitrage Sa boosted its stake in FFIV in the latest quarter, The investment management firm added 12,201 additional shares and now holds a total of 32,152 shares of F5 Networks which is valued at $4,035,076. F5 Networks makes up approx 0.02% of Bnp Paribas Arbitrage Sa’s portfolio.Independent Portfolio Consultants boosted its stake in FFIV in the latest quarter, The investment management firm added 190 additional shares and now holds a total of 5,774 shares of F5 Networks which is valued at $724,637. F5 Networks makes up approx 0.23% of Independent Portfolio Consultants’s portfolio.Washington Trust Bank boosted its stake in FFIV in the latest quarter, The investment management firm added 6 additional shares and now holds a total of 14,206 shares of F5 Networks which is valued at $1,782,853. F5 Networks makes up approx 0.43% of Washington Trust Bank’s portfolio.
F5 Networks closed down -1.42 points or -1.15% at $121.81 with 8,74,094 shares getting traded on Tuesday. Post opening the session at $123.22, the shares hit an intraday low of $121.22 and an intraday high of $123.3 and the price fluctuated in this range throughout the day.Shares ended Tuesday session in Red.
On the company’s financial health, F5 Networks reported $1.81 EPS for the quarter, beating the analyst consensus estimate by $ 0.02 according to the earnings call on Jul 20, 2016. Analyst had a consensus of $1.79. The company had revenue of $496.52 million for the quarter, compared to analysts expectations of $495.70 million. The company’s revenue was up 2.7% compared to the same quarter last year. During the same quarter in the previous year, the company posted $1.67 EPS.
Many Wall Street Analysts have commented on F5 Networks. Company shares were Initiated by Wunderlich on Jul 21, 2016 to “Buy”, Firm has raised the Price Target to $ 110 from a previous price target of $100 .F5 Networks was Downgraded by Credit Suisse to ” Neutral” on Jul 21, 2016. Company shares were Reiterated by RBC Capital Mkts on Jul 21, 2016 to “Sector Perform”, Firm has raised the Price Target to $ 120 from a previous price target of $115 .
F5 Networks . is the developer and provider of application delivery services. The Company’s core technology is a full-proxy programmable software platform called TMOS (Traffic Management Operating System). It helps organizations seamlessly scale cloud data center and software-defined networking deployments to successfully deliver applications to anyone anywhere at any time. It works with many technology companies to improve manageability strengthen security and ensure faster and more successful deployments. Its applications include availability and delivery. It can remove the roadblocks in one’s network to efficiently and securely deliver applications that are available to users when and where they need them. It can also accelerate one’s application response time minimize latency and delays and reduce the number of data round trips necessary to complete a web request.
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F5 Networks to Present at Investor and Technology Conferences from Morgan Keegan & Co., Oppenheimer & Co., Inc., and Can
F5Networks, . (NASDAQ: FFIV), the global leader in Application
Delivery Networking, today announced that company management will
participate in the Morgan Keegan’s 2009 "Summer in the City" Technology
Conference in New York on August 11, the Oppenheimer’s Annual
Communications & Technology Conference in Boston on August 12, and the
Canaccord Adams' 29th annual Global Growth Conference in Boston on
August 13.
F5’s presentation schedule is as follows:
August 11 at the Waldorf-Astoria Hotel (">301 Park Avenue, New York).
August 12 at the Four Seasons Hotel (200 Boylston Street, Boston).
Thursday, August 13 at the InterContinental Hotel (510 Atlantic
Avenue, Boston).
President and Chief Executive Officer, and Andy Reinland, SVP and Chief
Finance Officer.
Interested viewers can go to .f5maboutinvestor-relationsevents-calendar.html
to access a direct link to the webcasts for the presentations. Webcasts
will be accessible through September 14, 2009.
About F5 Networks
F5 Networks is a global leader in Application Delivery Networking (ADN),
focused on ensuring the secure, reliable, and fast delivery of
applications. F5’s flexible architectural framework enables
community-driven innovation that helps organizations enhance IT agility
and dynamically deliver services that generate true business value. F5’s
vision of unified application and data delivery offers customers an
unprecedented level of choice in how they deploy ADN solutions. It
redefines the management of application, server, storage, and network
resources, streamlining application delivery and reducing costs. Global
enterprise organizations, service and cloud providers, and Web 2.0
content providers worldwide trust F5 to keep their business moving
forward. For more information, go to .f5m.
F5 Investor Relations
John Eldridge, 206-272-6571
j.eldridgef5m
Speedy Web Content Delivery with CDNs
Express delivery to your Internet customersIn today's highly competitive e-business world, companies must deliver Web content faster than their competitors to attract and retain Internet customers. According to a study that Jupiter Research Center conducted in 2000, 7 percent of customers will abandon a Web page if the download time is less than 7 seconds, 30 percent will move on if the download time is 8 to 11 seconds, and 70 percent will leave the Web page if the download time is 12 seconds or longer.
To avoid losing customers because of slow download times and to improve customers’ Web surfing experience, many companies deploy load balancers to equalize the load among multiple Web servers in one site or across two or more sites. (For more information about load balancers, see "Web Server Load Balancers," April 2000.) Some companies place reverse proxy servers in front of Web servers to cache Web pages that external customers frequently access, and many companies use cache servers in their intranets to cache Web pages that their internal users frequently access. (For more information about Web caching, see "Surfing Web-Caching Technology, Part 1," September 1999, and "Surfing Web-Caching Technology, Part 2," October 1999.) Load balancers efficiently select the least-busy Web server among several mirrored servers to speed Web content retrieval. However, a load balancer doesn’t minimize the number of hops that content must make to reach a requesting user; the average number of hops between a browser or browser's cache server and a Web site is 17. So, many hops can degrade a company’s Internet-content delivery performance, even if the company’s Web site quickly retrieves the content and the customer has a fast Internet link. Even with a cache server, the hit ratio will be only about 40 percent. The other 60 percent of requests must travel to the originating Web server over the Internet.
To provide better quality and faster Web service, content providers want to put their content as close as possible to the customers who want it. Over the past 2 years, this concept has evolved into a new Web architecture and Internet service called Content Delivery Network or Content Distribution Network (CDN). The Internet Engineering Task Force (IETF) calls this new architecture a Content Network (CN).
A CDN is a smart, application-layer network that a CDN service provider builds on the Internet to guarantee high-performance content delivery. Organizations such as content providers and Web-hosting services can subscribe to CDN services—many organizations are already taking advantage of CDN’s benefits. The High Tech Resource Consulting Group, a market research firm, estimates that the CDN market will grow to $2.3 billion by 2002.
CDN Architecture and ServicesA CDN replicates a Web server’s content from the origin server (CDN terminology for the originating Web server) to the CDN's surrogates (i.e., content or cache servers) at various Points of Presence (POPs) near customers. A CDN POP often has multiple surrogates and uses a load balancer to spread the load among them.
When a customer requests content, the CDN directs the user's request to the nearest POP, whose load balancer forwards the request to the least-loaded surrogate. This surrogate retrieves the content from its cache and delivers the content through the load balancer to the customer. Figure 1 shows CDN architecture and the three major CDN functions: accounting, content distribution, and request routing.
AccountingAs Figure 1 shows, accounting takes place on the surrogate level. Each surrogate logs content usage, such as the speed (in megabits per second) with which the surrogate delivers content and the number of hits that particular content (i.e., a specific page or object) receives, and reports the usage information to a central accounting system. The CDN uses the gathered accounting information to charge subscribers, produce statistics for subscribers, and analyze the workload of surrogates and POPs.
Content DistributionA CDN can use two methods to distribute content from an origin server to surrogates: the Internet or satellite broadcast. Using the Internet to replicate content is the simple and natural choice. Distribution occurs when a company changes content on its origin Web server or when the CDN adds a new surrogate to the network. Because only one distribution takes place from the origin server to each surrogate per content change, the bandwidth consumption and workload for content distribution is almost nothing when compared with the number of content accesses and fetches each surrogate performs for requesting customers. Many CDN service providers, such as Akamai Technologies, Digital Island, and Mirror Image Internet, use the Internet for content distribution.
If a company’s origin server is far away from surrogate locations or slow links exist between the origin server and the surrogates, content distribution performance for rich content such as realtime streaming multimedia will be unpredictable. For such content, satellite broadcasting provides a high-performance transmission path from the origin server to remote surrogate locations. However, satellite broadcasting is an expensive solution. Using a satellite channel can cost hundreds of thousands of dollars per month. Despite this cost, several CDN service providers, such as Cidera and Loral CyberStar, use satellite broadcasting.
A CDN uses either the push or pull method to maintain up-to-date replicated content on its surrogates. In the push method, a content distribution controller monitors content on the origin server. When a change occurs, the controller copies and synchronizes the change from the origin server to remote surrogates. Consequently, the surrogates always contain up-to-date content. Several CDN service providers, such as Mirror Image Internet, use the content push method.
A content distribution controller can be a hardware appliance (e.g., F5 Networks' GLOBAL-SITE Controller) or a software package (e.g., Inktomi's Content Delivery Suite) that can run on a dedicated server or on the origin server. With either the hardware or software content-distribution solution, you can specify which files, pages, objects, and applications on the origin server you want the controller to replicate, to which surrogates, and under what conditions. A content distribution controller can publish content to popular Web server software-based servers, such as Apache, Microsoft IIS, and Netscape Enterprise Server. However, controllers often require that surrogates run the associated surrogate product from the controller’s vendor. For example, F5 Networks' GLOBAL-SITE Controller works with F5 Networks' EDGE-FX Cache, and Inktomi's Content Delivery Suite works with Inktomi's Traffic Server. Some vendors have been working together to improve CDN product interoperability. In April 2001, F5 Networks and Inktomi announced a strategic alliance to integrate their CDN products.
In contrast to CDNs that use the push method, CDNs that use the content pull method don't have a dedicated content distribution controller to push the changed content to surrogates. When a CDN’s request-routing system directs a customer's request to a specific surrogate, the surrogate retrieves the locally cached content and passes it to the user. If the content isn’t cached locally on the surrogate, the surrogate fetches the requested content from the origin Web server.
Surrogates that use the pull method work like ordinary cache servers. The surrogates update cached content by checking for content changes on the origin server, and they purge cached content that users haven’t requested in a long time. Most CDN product manufacturers offer a cache server-based surrogate in their product lines (e.g., CacheFlow's Edge Accelerator and Server Accelerator, Network Appliance's NetCache, F5 Networks’ EDGE-FX Cache, Inktomi's Traffic Server). Most CDN service providers use the content pull method.
Although the pull method doesn’t provide as high a content hit ratio as the push method does, the hit ratio can still approach 100 percent, and a pull-method CDN will be much faster than a typical cache system. If a surrogate’s average hit ratio is 99 percent and we assume that content delivery time is 0.1 second for a hit and 8 seconds for a miss, then the average content delivery time for a CDN surrogate is 0.179 seconds. If the average hit ratio on a typical non-CDN cache server is 40 percent and we assume the same content delivery times that we assume for the CDN surrogate, then the average content delivery time for a non-CDN cache server is 4.84 seconds. Therefore, a pull-method CDN delivers content about 27 times as fast as a typical cache system.
Request RoutingAnother important CDN service is request routing (aka content redirection and content routing), which directs users’ requests to an appropriate surrogate. A CDN request-routing system selects a surrogate according to various criteria, such as proximity of the surrogate network to the user, surrogate load, and content availability. The IETF recently studied CDNs’ request-routing techniques and concluded that CDNs use three primary request-routing mechanisms: DNS, transport-layer, and application-layer request routing. (To read the IETF report, click here.) CDNs can implement a combination of all three types.
DNS request routing. When a client requests content from a Web site, the client first needs to resolve the content server’s IP address through DNS. A local DNS server answers the client's query by returning an A record for the site. This A record contains the IP addresses for one or more selected surrogates. If the client receives more than one IP address, the client chooses a surrogate in a round-robin fashion. If a CDN uses a load balancer in the POP, the IP address in the A record is a virtual IP (VIP) address. CDNs often use smart servers, which have more capabilities than a BIND or Microsoft DNS server and direct users’ requests to the most appropriate surrogate.
Suppose examplem, a CDN subscriber, has delegated the subdomain .examplem from its authoritative DNS server to the CDN's smart DNS server so that the smart DNS server can control surrogate selection for .examplem. Figure 2 illustrates the following steps in smart DNS request routing:
After the DNS request-routing system chooses a surrogate for a user's initial connection and directs the user to the surrogate, a transport-layer request-routing system examines the first packet of the user request to determine whether the chosen surrogate is optimal for the user. Each POP includes a transport-layer request-routing system that vendors usually implement in the load balancer. Based on the information in the first packet, including the IP address, port number, transport-layer protocol, and user policy and performance metrics, the transport-layer request-routing system determines whether it needs to select a more suitable surrogate POP for the user request.
Figure 3 illustrates triangulation, a common implementation of transport-layer request routing. After a user receives a VIP for a surrogate in the CDN’s POP1, the user sends a content request to the surrogate. POP1's transport-layer request-routing system uses the information in the user’s first packet to determine that POP2 can better fulfill the user's request (e.g., POP2 might provide the user better ftp download capabilities). POP1 then forwards the request to POP2's transport-layer request-routing system. POP2 recognizes that the arriving request is from POP1's transport-layer request-routing system. After POP2 fetches the requested content, POP2's transport-layer request-routing system changes the source IP address in the content packet’s IP header to POP1's VIP address and sends the packet to the user. When the user receives the packet, the user thinks the packet is from POP1. The user continues sending requests to POP1 until the session finishes. Triangulation redirection works well because upstream traffic from users is light compared with downstream traffic from a POP. Using triangulation to provide a more efficient downstream path for user requests improves content-delivery performance.
Application-layer request routing. An application-layer request-routing system conducts a deeper inspection of the user request by checking the application information beyond the transport layer in the received packet. This examination lets the application-layer request-routing system determine the best surrogate for a user request based on information at the individual-object level. For example, when a user requests a news page that contains news items, graphics, and advertisements, the application-layer request-routing system can redirect the user to retrieve each object from the best surrogate. Three major methods for implementing application-layer request-routing systems exist: header inspection, HTTP and Real Time Streaming Protocol (RTSP) redirection, and content modification.
In the header of a session request, HTTP, RTSP, and Secure Sockets Layer (SSL) applications provide useful information, such as a URL, cookie, session identifier, site specification, or language specification. For example, an SSL session requires a persistent connection between a user and the surrogate running the SSL application. By inspecting the user information in the user’s cookie or the surrogate information in the SSL session identifier, an application-layer request-routing system can direct the user’s requests to the same surrogate for the entire session.
Alternatively, an application-layer request-routing system can use HTTP and RTSP redirection to redirect a user’s GET request to another surrogate. If a user requests information from a surrogate that’s overloaded or down, the application-layer request-routing system responds to the user’s GET request with a ">301 (moved temporarily) or 302 (moved permanently) code message that includes the IP address of the surrogate with which the user was communicating. The user’s browser can then initiate a new session.
The third method, content modification, lets a content provider control request-routing decisions. When the content provider subscribes to a CDN service, the content provider rewrites URLs on the origin server. For example, an HTML Web page often contains plaintext as well as embedded objects such as graphics and images. The Web page uses embedded HTML directives in the form of URLs to reference the embedded objects. Usually, the embedded URLs point to the embedded objects on the same origin server that contains the Web page. However, to take advantage of a CDN service, the content provider can change the embedded URLs to CDN URLs so that the CDN service can deliver bandwidth-sensitive objects such as graphics, images, and streaming multimedia.
As Figure 4 shows, when a user requests a Web page, the request goes to the origin server first. The origin server returns to the user the HTML Web page with the embedded CDN URLs. The user then retrieves the embedded objects from the CDN. The user must resolve the domain name in a CDN URL so that the CDN can use DNS request routing to select an optimal POP and surrogate to fulfill the user request. The CDN then uses transport- and application-layer request routing to redirect the user’s request to the best POP or surrogate.
When content changes on the origin server, the content provider can use a software utility to manually or automatically rewrite embedded URLs on the origin server. An example of application-layer request routing that uses content modification is Akamai's FreeFlow content delivery service. Akamai’s FreeFlow Akamaizer software tool can automate URL modification.
CDN PeeringA CDN can quickly deliver content to users close to the CDN’s surrogates. However, no CDN can cover all the networks across the Internet. Thus, to offer fast content delivery to geographically disparate users, a content provider must subscribe to multiple CDN services.
To expand their services globally over more networks, CDNs need to link together and deliver content for each other’s customers as well as for their own. This implementation is called CDN peering or content peering.
Content delivery across multiple CDNs isn’t simple. When a user requests content that requires the involvement of two or more CDNs, the CDNs’ request-routing systems must work together to determine the best CDN for the user request. In August 2000, several vendors formed two industry alliances—Content Alliance and Content Bridge—to help develop CDN peering. To develop content peering architecture and standards, IETF formed the Content Distribution Internetworking Group in December 2000. The group includes members from both alliances and has published several drafts about content peering architecture and standards. In January 2001, Content Bridge began delivering its content peering service, in which a content provider can access the services of any Content Bridge member by subscribing to CDN service from one vendor in the alliance.
CDN services that have a content peering agreement must share core CDN services, including content distribution and request routing. To do so, CDNs use a Content Peering Gateway (CPG) service to link services to one another. The CPG provides the peering functionality. Figure 5 shows an example CDN peering architecture that involves three CDNs.
Through content distribution peering, a CDN can redistribute the content from a content provider’s origin server to other CDNs’ CPGs. In turn, these CPGs pass the content to the necessary surrogates. To distribute content, peering CDNs can use either the push or pull method. For multiple CDNs to be able to deliver content, the peering CDNs’ request-routing systems must work together to serve the content’s namespace. For this setup to work, a content provider must delegate authority for its content URLs to an authoritative request-routing system on the CPG of the CDN to which the content provider subscribes. This authoritative request-routing system further delegates authority to the request-routing systems of all peering CDNs. For DNS request routing, the content provider delegates a subdomain to the authoritative request-routing DNS server, which in turn delegates the subdomain to the request-routing DNS servers of peering CDNs.
When a CDN’s authoritative request-routing system receives a user request, it negotiates with all peering CDN CPGs to determine which CDN should serve the request. The request-routing system then directs the user request to that CDN. The selected CDN uses its internal request-routing mechanism, which is transparent to the authoritative request-routing system and other CDNs, to determine which surrogate should deliver the content to the user. The selected surrogate then delivers the requested content to the user. At the same time, the surrogate reports the accounting information for the delivered content to the accounting system of the surrogate’s CDN. One CDN can request accounting information from or send it to another CDN through the CPG accounting peering function. A billing organization, such as a third-party clearinghouse firm, handles the charge and payment process of content delivery among peering CDNs.
Content Meets Express DeliveryCDN technology is brand new. However, the number of organizations that use CDNs is growing quickly. During an online CDN seminar in March 2001, Content Bridge conducted a survey about which techniques organizations had used to improve content delivery performance. The survey results showed that 25 percent of seminar participants had used CDNs, 15.6 percent had deployed cache servers, 34.4 percent had used mirrored servers, and the remaining 25 percent had tried all three methods.
CDNs are still mainly proprietary services. However, industry alliances and IETF are developing CDN peering architecture and standards that will eventually evolve into a public network in which multivendor products and services use Internet CDN standards to interoperate. Are you ready for your Web content to meet express Internet delivery services?
Cisco Rivals Trade Near 52-Week Highs
Posted on Friday, Nov 26th 2010Cisco recently provided a grim outlook that was far short of analyst estimates. However, its rivals Juniper, F5, and Polycom reported strong results and provided outlooks close to analyst estimates. They are trading close to 52-week highs, while Cisco is close to its 52-week low. Let’s take a closer look.
Juniper’s FinancialsJuniper reported third quarter revenue of $1.012 billion, up 23% but missing analyst estimates of $1.03 billion. Net income was $134.5 million, or $0.25 per share, versus $83.78 million or $0.16 per share last year. The company ended the quarter with nearly $2.7 billion in total cash and investments and repurchased shares for $135 million.
For the fourth quarter, Juniper expects revenue of $1.12 billion, plus or minus $20 million and non-GAAP EPS of $0.35 to $0.37. Analysts expect EPS of $0.35 on revenue of $1.1 billion. The stock is trading around $34.35 with market cap of about $18 billion. It hit a 52-week high of $36.00 on November 12 and a 52-week low of $23.03 on June 29.
Recent Acquisitions By JuniperLast week, Juniper announced its plans to buy Trapeze Networks for $152 million and the intellectual property assets of Internet video storage and delivery technology company Blackwave for an undisclosed sum. Trapeze Networks is a technology leader in enterprise wireless local area network (WLAN) systems and management software. A recent report by Dell’Oro Group estimates that the enterprise WLAN technology market will grow from $2.2 billion in 2010 to $3.4 billion in 2014. The acquisition will make WLAN infrastructure a key part of Juniper’s portfolio, accelerating the company’s growth in the enterprise market and advancing its vision for the new network. This vision is centered on two significant market trends, mobile Internet and cloud computing. Security is also a critical element of the mobile Internet. Earlier in the quarter, Juniper acquired SMobile Systems, ., a privately held software company focused solely on smartphone and tablet security solutions for the enterprise, service provider, and consumer markets, for $69 million.
Polycom’s FinancialsPolycom (NASDAQ:PLCM), with annual revenue of $967 million, reported third quarter revenue of $308 million, up 27%. Net income was $17 million or $0.20 per share compared to $14 million or $0.16 per share last year. Non-GAAP EPS was $0.38 versus analyst estimates of $0.36 on revenue of $">301 million. Gross margin increased more than one point sequentially and more than two points year-over-year driven by network systems growth. Polycom ended the quarter with $500 million in cash and investments and no debt.
For the fourth quarter, Polycom expects revenue to grow 5% to 7% sequentially or $323.5 million to $329.5 million, beating analyst estimates of $317 million.
Polycom faces stiff competition from Cisco, which recently acquired its rival Tandberg, which held about 31% share in 2009. Cisco recently launched a home video conferencing product, ?mi, priced at $599 to expand its consumer presence. In response to this, Polycom has announced its plans to release videoconferencing applications for Samsung’s Galaxy platform, which powers its Galaxy S smartphone and Galaxy Tab tablet. Sayantani Ghosh of Reuters reports that
“Polycom has similar apps lined up for BlackBerry, Windows Mobile 7, Apple and other Android-based devices, and is hoping to launch these through 2011. Polycom is also talking to consumer-electronics makers to add low-latency video to home devices and is working with “at least one major carrier on a home telepresence system.”
Polycom is trading around $36.76, a three-year high, with market cap of about $3.14 billion.
There has been much M&A activity in the video conferencing sector over the last year. Apart from Cisco’s $3.3 billion Tandberg acquisition, there is LifeSize, which holds about 5.6% of the market. Polycom, the market leader with 35% share, is an attractive acquisition prospect for either HP or Juniper, which are looking to expand their presence in this active sector. The videoconferencing market grew over 5% in 2009 to about $1.7 billion, and Gartner expects the market to reach $8.6 billion by 2013.
F5’s FinancialsUnlike in the video conferencing industry, F5 (NASDAQ:FFIV) doesn’t face much competitive pressure from Cisco, whose focus lies elsewhere, leaving F5 to continue dominating this area. Cloud computing, virtualization, and mobile applications are some of the trends that are driving F5’s growth. F5 reported fourth quarter revenue of $254.3 million, up 45.2% and beating estimates of $248 million. Net income was $48.2 million or $0.59 per diluted share compared to $28.4 million or $0.36 per diluted share last year. F5 ended the year with $862 million in cash and investments after repurchasing $75 million of common stock. Its board of directors also approved a new program to repurchase up to $200 million of the company’s outstanding common stock.
For fiscal year 2010, revenue was $882.0 million, up 35% from $653.1 million in fiscal year 2009. Net income for the year was $151.2 million ($1.86 per diluted share) versus $91.5 million ($1.14 per diluted share) in fiscal year 2009.
For the first quarter, F5 expects revenue of $265 million to $270 million with a GAAP earnings target of $0.62 to $0.64 per diluted share. Analysts expect earnings of $0.73 a share on revenue of $259.8 million. The stock is trading around $132 with market cap of about $10 billion. It hit a 52-week high of $133.70 on November 24.
F5 Gains ADC Market Share at Cisco’s CostAccording to market research firm Infonetics Research, the application delivery controller (ADC) market is back on a growth track after a tumultuous 2009, with worldwide sales up 28% compared to the first quarter of last year.
Saqib Iqbal Ahmed of Reuters reports that
F5 Networks, which had received a takeover overture last year, remains a potential target for technology giants, including IBM, Dell, HP, Oracle, Juniper and Cisco. F5 leads the ADC market and has an almost 20-point lead over Cisco. It gained 8% market share in the recent quarter, half of which came from Cisco.
Cisco’s poor outlook this quarter led to concerns that it was losing its focus in its core routing and switching business while trying to expand in its 30 adjacent markets. However, Jim Duffy of Network World reports that
“Cisco maintained its 72% share of the overall Ethernet switch market and even upped that by 2% from last year. HP and Juniper also gained share sequentially and over the year. HP now stands at 10.5%, from 6.5% a year ago (thanks, 3Com); and Juniper is now just under 2% from 1.3% last year. Share losers during the quarter, both on a sequential and year-over-year basis, were Brocade, Extreme, Avaya, Alcatel-Lucent and Huawei, according to UBS. HP and Juniper share gains seem to be coming from this group rather than from Cisco.”
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