WAN Optimization
Encyclopedia
WAN optimization is a collection of techniques for increasing data-transfer efficiencies across wide-area networks. In 2008, the WAN optimization market was estimated to be $1 billion , and it will grow to $4.4 billion according to Gartner, a technology research firm.
The most common measures of TCP data-transfer efficiencies (i.e., optimization) are throughput, bandwidth requirements, latency, protocol optimization, and congestion, as manifested in dropped packets. In addition, the WAN itself can be classified with regards to the distance between endpoints and the amounts of data transferred. Two common business WAN topologies are Branch to Headquarters and Data Center
to Data Center. In general, "Branch" WAN links are closer, use less bandwidth, support more simultaneous connections, support smaller connections and more short-lived connections, and handle a greater variety of protocols. They are used for business applications such as email, content management systems, database application, and Web delivery. In comparison, "DC2DC" WAN links tend to require more bandwidth, are more distant, and involve fewer connections, but those connections are bigger (100Mbps to 1Gbps flows) and of longer duration. Traffic on a "DC2DC" WAN may include replication, back up, data migration, virtualization, and other Business Continuity/Disaster Recovery BC/DR flows.
WAN optimization has been the subject of extensive academic research almost since the advent of the WAN. In the early 2000s, research in both the private and public sectors turned to improving the end-to-end throughput of TCP, and the target of the first proprietary
WAN optimization solutions was the Branch WAN. In recent years, however, the rapid growth of digital data, and the concomitant needs to store and protect it, has presented a need for DC2DC WAN optimization.
Component techniques of Branch WAN Optimization include deduplication, WAFS
, CIFS proxy, HTTPS Proxy, media multicast
ing, Web caching, and bandwidth management
. Requirements for DC2DC WAN Optimization also center around deduplication and TCP acceleration, however these must occur in the context of multi-gigabit data transfer rates.
The most common measures of TCP data-transfer efficiencies (i.e., optimization) are throughput, bandwidth requirements, latency, protocol optimization, and congestion, as manifested in dropped packets. In addition, the WAN itself can be classified with regards to the distance between endpoints and the amounts of data transferred. Two common business WAN topologies are Branch to Headquarters and Data Center
Data center
A data center is a facility used to house computer systems and associated components, such as telecommunications and storage systems...
to Data Center. In general, "Branch" WAN links are closer, use less bandwidth, support more simultaneous connections, support smaller connections and more short-lived connections, and handle a greater variety of protocols. They are used for business applications such as email, content management systems, database application, and Web delivery. In comparison, "DC2DC" WAN links tend to require more bandwidth, are more distant, and involve fewer connections, but those connections are bigger (100Mbps to 1Gbps flows) and of longer duration. Traffic on a "DC2DC" WAN may include replication, back up, data migration, virtualization, and other Business Continuity/Disaster Recovery BC/DR flows.
WAN optimization has been the subject of extensive academic research almost since the advent of the WAN. In the early 2000s, research in both the private and public sectors turned to improving the end-to-end throughput of TCP, and the target of the first proprietary
Proprietary software
Proprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
WAN optimization solutions was the Branch WAN. In recent years, however, the rapid growth of digital data, and the concomitant needs to store and protect it, has presented a need for DC2DC WAN optimization.
Component techniques of Branch WAN Optimization include deduplication, WAFS
Wide area file services
Wide area file services products allow remote office users to access and share files globally at LAN speeds over the WAN. Distributed enterprises that deploy WAFS solutions are able to consolidate storage to corporate datacenters, eliminating the need to back up and manage data that previously...
, CIFS proxy, HTTPS Proxy, media multicast
Multicast
In computer networking, multicast is the delivery of a message or information to a group of destination computers simultaneously in a single transmission from the source creating copies automatically in other network elements, such as routers, only when the topology of the network requires...
ing, Web caching, and bandwidth management
Bandwidth management
Bandwidth management is the process of measuring and controlling the communications on a network link, to avoid filling the link to capacity or overfilling the link, which would result in network congestion and poor performance of the network.- Management :Bandwidth management mechanisms may be...
. Requirements for DC2DC WAN Optimization also center around deduplication and TCP acceleration, however these must occur in the context of multi-gigabit data transfer rates.
WAN optimization techniques
- Deduplication - Eliminates the transfer of redundant data across the WAN by sending references instead of the actual data. By working at the byte level, benefits are achieved across IP applications.
- Compression - Relies on data patterns that can be represented more efficiently. Essentially compression techniques similar to ZIP, RAR, ARJ etc are applied on-the-fly to data passing through hardware (or virtual machine) based WAN acceleration appliances.
- Latency optimization - Can include TCP refinements such as window-size scaling, selective Acknowledgements, Layer 3 congestion control algorithms, and even co-location strategies in which the application is placed in near proximity to the endpoint to reduce latency. In some implementations, the local WAN optimizer will answer the requests of the client locally instead of forwarding the request to the remote server in order to leverage write-behind and read-ahead mechanisms to reduce WAN latency.
- Caching/proxy - Staging data in local cacheCacheIn computer engineering, a cache is a component that transparently stores data so that future requests for that data can be served faster. The data that is stored within a cache might be values that have been computed earlier or duplicates of original values that are stored elsewhere...
s; Relies on human behavior, accessing the same data over and over.
- Forward error correctionForward error correctionIn telecommunication, information theory, and coding theory, forward error correction or channel coding is a technique used for controlling errors in data transmission over unreliable or noisy communication channels....
- mitigates packet loss by adding an additional loss-recovery packet for every “N” packets that are sent, and this would reduce the need for retransmissions in error-prone and congested WAN links.
- Protocol spoofingProtocol spoofingProtocol spoofing is used in data communications to improve performance in situations where an existing protocol is inadequate, for example due to long delays or high error rates....
- Bundles multiple requests from chatty applications into one. May also include stream-lining protocols such as CIFS.
- Traffic shapingTraffic shapingTraffic shaping is the control of computer network traffic in order to optimize or guarantee performance, improve latency, and/or increase usable bandwidth for some kinds of packets by delaying other kinds of packets that meet certain criteria...
- Controls data flow for specific applications. Giving flexibility to network operators/network admins to decide which applications take precedence over the WAN. A common use case of traffic shaping would be to prevent one protocol or application from hogging or flooding a link over other protocols deemed more important by the business/administrator. Some WAN acceleration devices are able to traffic shape with granularity far beyond traditional network devices. Such as shaping traffic on a per user AND per application basis simultaneously.
- Equalizing - Makes assumptions on what needs immediate priority based on the data usage. Excellent choice for wide open unregulated Internet connections and clogged VPN tunnels.
- Connection limits - Prevents access gridlock in routers and access points due to denial of service or peer to peer. Best suited for wide open Internet access links, can also be used on WAN links.
- Simple rate limits - Prevents one user from getting more than a fixed amount of data. Best suited as a stop gap first effort for a remediating a congested Internet connection or WAN link.
Products and companies implementing WAN optimization
- AppEx NetworksAppEx NetworksAppEx Networks is a privately-held WAN optimization and ADN company headquartered in Cupertino, California, with an R&D center in Beijing, China. AppEx manufactures networks appliances based on its patented technologies, and delivers WAN optimization, ADN and traffic management solutions...
- ApplianSysApplianSysApplianSys, founded in 2000, is a privately held venture capital-backed technology company based in London, United Kingdom. It designs, builds and markets Internet server appliances that are deployed in more than 80 countries...
- AryakaAryakaAryaka is a technology company that provides cloud-based WAN optimization and application acceleration services. The company is headquartered in Milpitas, California with development offices in Bangalore, India and has 100+ employees....
- Black Box CorporationBlack Box CorporationBlack Box Corporation, d/b/a Black Box Network Services, is headquartered in the Pittsburgh suburb of Lawrence, Pennsylvania, USA. The company is a provider of communications and infrastructure solutions...
- BluecoatBlue Coat SystemsBlue Coat Systems Inc. is a network security and network management company based in Sunnyvale, California, United States.It identifies itself as an application delivery network specialist...
- CiscoCiscoCisco may refer to:Companies:*Cisco Systems, a computer networking company* Certis CISCO, corporatised entity of the former Commercial and Industrial Security Corporation in Singapore...
- Citrix
- Expand NetworksExpand NetworksExpand Networks, Ltd., based in Tel Aviv, Israel, is a provider of WAN Optimization solutions.- About :Expand Networks is privately held. The company was founded in 1998; initial financing was provided by Discount Investment Corporation, The Eurocom Group, Ophir Holdings, and a private group of...
- ExindaExindaExinda is a United States technology company that provides computer networking products and services. Headquartered in Andover, Massachusetts, Exinda delivers WAN optimization and network bandwidth management solutions to small and medium-sized enterprises....
- Infineta SystemsInfineta SystemsInfineta Systems is an Information Technology company that makes WAN optimization products for high performance, latency-sensitive network applications. The company’s flagship product, the Data Mobility Switch , makes it possible for application throughput to exceed the nominal bandwidth of the...
- InternapInternapFounded in May 1996 in Seattle, Internap Network Services Corporation is a publicly traded company headquartered in Atlanta, Georgia that enables route-optimized delivery of content over the Internet. Internap’s business units include Internet Protocol , data center and Content Delivery Network ...
- Ipanema TechnologiesIpanema Technologies- Company Information :Ipanema Technologies’ is an I.T. company founded in 1999 by Jean-Yves Leclerc,Thierry Grenot and François Lecerf. They develop systems for application traffic management, WAN visibility, WAN optimization, WAN acceleration, WAN control and Wan governance.They are...
- Juniper NetworksJuniper NetworksJuniper Networks is an information technology and computer networking products multinational company, founded in 1996. It is head quartered in Sunnyvale, California, USA. The company designs and sells high-performance Internet Protocol network products and services...
- RadwareRadwareRadware , is a provider of integrated Application delivery, Network Security and Load balancing solutions based in Tel Aviv, Israel. Radware, which is a member of the Rad Group of companies, is a public company and its shares are traded on NASDAQ.- History :...
- Riverbed TechnologyRiverbed TechnologyRiverbed Technology is a technology company that specializes in improving the performance of networks and networked applications. It was founded May 23, 2002 by Jerry Kennelly and Steve McCanne in San Francisco, California where its world headquarters remains...
- Silver Peak SystemsSilver Peak SystemsSilver Peak Systems designs and manufactures WAN optimization products. Silver Peak's global headquarters is located in Santa Clara, California. Silver Peak was founded in 2004 by David Hughes, who holds a PhD from Wollongong University and has been awarded 35 patents...
- StreamcoreStreamcoreStreamcore is an information technology company specializing in Quality of Service , controlling/monitoring Unified Communications and application delivery management over the Wide area network . Its headquarters are located in Puteaux, France, with offices in Germany, Africa, and the Middle...
- UDcastUDcastUDcast is a provider of solutions enabling full Internet Protocol over broadcast media, in the areas of IP networks over satellite andservers for DVB-H, DVB-SH, ATSC and WiMAX standards compliant television on mobile networks....