Cerent Corporation was an optical equipment maker based in Petaluma, California. It was founded in 1997 as Fiberlane Communications with funding from Kleiner Perkins Caufield & Byers and Vinod Khosla as the managing VC. The company was founded with three divisions: Systems in Petaluma, Chip Design in Mountain View, California and Network Management Systems in Burnaby, British Columbia. In early 1998 the company split into two companies with the Petaluma branch becoming Cerent and the Burnaby and Mountain View branches becoming Siara Systems (Acquired by Redback Networks in 1999). [1]
Cerent's first product was the Cerent 454 (later the Cisco 15454). The Cerent 454 was a second generation SONET ADM (Add-Drop Multiplexor) that also supported TCP/IP data switching. When operating as a pure ADM, the 454 could add and drop circuits from OC-192 down to Digital Signal 1 (DS1) -- later it would support wavelength-division multiplexing (WDM). Unlike the ADMs that preceded it, a transport signal did not have to be terminated outside the box to switch or route the TCP/IP packets. "Data cards" could be inserted into the chassis which would terminate the circuits then switch or route the packets between those terminated circuits. This capability meant carriers no longer had to purchase two boxes (e.g. an ADM and a router) just to move TCP/IP packets around its telecom network.
Other advantages of the Cerent 454 included: smaller form factor, higher port density, greater chip integration, and lower power consumption than competitors at the time.[ citation needed ] The unit also was one of the first network elements to utilize TCP/IP and a web server on its management interface (the first TCP/IP management network was Ditech Communications in its DWDM system, marketed in 1996) meaning it could be managed over a standard TCP/IP network as opposed to a more restrictive OSI network interface which was the standard in telecom networks at the time. This decision, while initially controversial, was promoted by Chip Roberson, for two pragmatic reasons: first, a TCP/IP stack came packaged with the embedded operating system from Wind River Systems and, second, the cost to acquire, test and support an OSI stack and associated network was comparatively cost-prohibitive for a young startup.
The primary founders of the company were: Raj Singh, Jay Sethuram, Ajaib Bhadare and Paul Elliott. The rest of the founding team (as of funding by Kleiner Perkins Caufield & Byers) consisted of:
The founding board of directors was: Raj Singh, Vinod Nair and Don Green (often referred to as "The Father of Telecom Valley").[ citation needed ]
Mike Hatfield soon after joined the team as CEO, replacing Raj Singh.[ citation needed ]
In August 1999, the company was sold to Cisco Systems for $7.2 billion [2] and became the foundation of Cisco's Optical Transport Business Unit. [3] The Cerent 454 was rebranded the Cisco 15454 and became the fastest product (at that time) to hit the $1B annual sales rate by selling $250 million in its second quarter as a Cisco business unit.
In November 1999, Redback bought Siara Systems for $4.3 billion. [4]
Internetworking is the practice of interconnecting multiple computer networks, such that any pair of hosts in the connected networks can exchange messages irrespective of their hardware-level networking technology. The resulting system of interconnected networks is called an internetwork, or simply an internet.
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The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suite are the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and the Internet Protocol (IP). Early versions of this networking model were known as the Department of Defense (DoD) model because the research and development were funded by the United States Department of Defense through DARPA.
A network service access point address, defined in ISO/IEC 8348, is an identifying label for a service access point (SAP) used in OSI networking.
The Open Systems Interconnection (OSI) model is a reference model from the International Organization for Standardization (ISO) that "provides a common basis for the coordination of standards development for the purpose of systems interconnection." In the OSI reference model, the communications between systems are split into seven different abstraction layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.
X.25 is an ITU-T standard protocol suite for packet-switched data communication in wide area networks (WAN). It was originally defined by the International Telegraph and Telephone Consultative Committee in a series of drafts and finalized in a publication known as The Orange Book in 1976.
Xerox Network Systems (XNS) is a computer networking protocol suite developed by Xerox within the Xerox Network Systems Architecture. It provided general purpose network communications, internetwork routing and packet delivery, and higher level functions such as a reliable stream, and remote procedure calls. XNS predated and influenced the development of the Open Systems Interconnection (OSI) networking model, and was very influential in local area networking designs during the 1980s.
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Virtual private network (VPN) is a network architecture for virtually extending a private network across one or multiple other networks which are either untrusted or need to be isolated.
The data link layer, or layer 2, is the second layer of the seven-layer OSI model of computer networking. This layer is the protocol layer that transfers data between nodes on a network segment across the physical layer. The data link layer provides the functional and procedural means to transfer data between network entities and may also provide the means to detect and possibly correct errors that can occur in the physical layer.
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SOCKS is an Internet protocol that exchanges network packets between a client and server through a proxy server. SOCKS5 optionally provides authentication so only authorized users may access a server. Practically, a SOCKS server proxies TCP connections to an arbitrary IP address, and provides a means for UDP packets to be forwarded. A SOCKS server accepts incoming client connection on TCP port 1080, as defined in RFC 1928.
Kleiner Perkins, formerly Kleiner Perkins Caufield & Byers (KPCB), is an American venture capital firm which specializes in investing in incubation, early stage and growth companies. Since its founding in 1972, the firm has backed entrepreneurs in over 900 ventures, including America Online, Amazon.com, Tandem Computers, Compaq, Electronic Arts, JD.com, Square, Genentech, Google, Netscape, Sun Microsystems, Nest, Palo Alto Networks, Synack, Snap, AppDynamics, and Twitter. By 2019 it had raised around $9 billion in 19 venture capital funds and four growth funds.
Deep packet inspection (DPI) is a type of data processing that inspects in detail the data being sent over a computer network, and may take actions such as alerting, blocking, re-routing, or logging it accordingly. Deep packet inspection is often used for baselining application behavior, analyzing network usage, troubleshooting network performance, ensuring that data is in the correct format, checking for malicious code, eavesdropping, and internet censorship, among other purposes. There are multiple headers for IP packets; network equipment only needs to use the first of these for normal operation, but use of the second header is normally considered to be shallow packet inspection despite this definition.
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Local Area Transport (LAT) is a non-routable networking technology developed by Digital Equipment Corporation to provide connection between the DECserver terminal servers and Digital's VAX and Alpha and MIPS host computers via Ethernet, giving communication between those hosts and serial devices such as video terminals and printers. The protocol itself was designed in such a manner as to maximize packet efficiency over Ethernet by bundling multiple characters from multiple ports into a single packet for Ethernet transport.
A network socket is a software structure within a network node of a computer network that serves as an endpoint for sending and receiving data across the network. The structure and properties of a socket are defined by an application programming interface (API) for the networking architecture. Sockets are created only during the lifetime of a process of an application running in the node.
A routing protocol specifies how routers communicate with each other to distribute information that enables them to select paths between nodes on a computer network. Routers perform the traffic directing functions on the Internet; data packets are forwarded through the networks of the internet from router to router until they reach their destination computer. Routing algorithms determine the specific choice of route. Each router has a prior knowledge only of networks attached to it directly. A routing protocol shares this information first among immediate neighbors, and then throughout the network. This way, routers gain knowledge of the topology of the network. The ability of routing protocols to dynamically adjust to changing conditions such as disabled connections and components and route data around obstructions is what gives the Internet its fault tolerance and high availability.
The Protocol Wars were a long-running debate in computer science that occurred from the 1970s to the 1990s, when engineers, organizations and nations became polarized over the issue of which communication protocol would result in the best and most robust networks. This culminated in the Internet–OSI Standards War in the 1980s and early 1990s, which was ultimately "won" by the Internet protocol suite (TCP/IP) by the mid-1990s when it became the dominant protocol suite through rapid adoption of the Internet.