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Nexus 7000
The Cisco Nexus series switches are modular and fixed port network switches designed for the data center. Cisco Systems introduced the Nexus Series of switches on January 28, 2008. The first chassis in the Nexus 7000 family is a 10-slot chassis with two supervisor engine slots and eight I/O module slots at the front, as well as five crossbar switch fabric modules at the rear. Beside the Nexus 7000 there are also other models in the Nexus range. All switches in the Nexus range run the modular NX-OS firmware/operating system on the fabric. NX-OS has some high-availability features compared to the well-known Cisco IOS. This platform is optimized for high-density 10 Gigabit Ethernet. The Nexus switching range Cisco Nexus OS Software Defined Networking (SDN) allows the same policies that govern Identity and Access Management (IAM) to dictate levels of access to applications and data through a totally converged infrastructure not possible with legacy network and system access methods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Switch
A network switch (also called switching hub, bridging hub, Ethernet switch, and, by the IEEE, MAC bridge) is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destination device. A network switch is a multiport network bridge that uses MAC addresses to forward data at the data link layer (layer 2) of the OSI model. Some switches can also forward data at the network layer (layer 3) by additionally incorporating routing functionality. Such switches are commonly known as layer-3 switches or multilayer switches. Switches for Ethernet are the most common form of network switch. The first MAC Bridge was invented in 1983 by Mark Kempf, an engineer in the Networking Advanced Development group of Digital Equipment Corporation. The first 2 port Bridge product (LANBridge 100) was introduced by that company shortly after. The company subsequently produced multi-port switches for both Ethernet and FDDI such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rack Unit
A rack unit (abbreviated U or RU) is a unit of measure defined as . It is most frequently used as a measurement of the overall height of 19-inch and 23-inch rack frames, as well as the height of equipment that mounts in these frames, whereby the height of the frame or equipment is expressed as multiples of rack units. For example, a typical full-size rack cage is 42U high, while equipment is typically 1U, 2U, 3U, or 4U high. Definition The rack unit size is based on a standard rack specification as defined in EIA-310. The Eurocard specifies a standard rack unit as the unit of height; it also defines a similar unit, horizontal pitch (HP), used to measure the width of rack-mounted equipment. The standard was adopted worldwide as ''IEC 60297 Mechanical structures for electronic equipment – Dimensions of mechanical structures of the series'', and defines the sizes for rack, subrack (a shelf-like chassis in which cards can be inserted), and the pitch of printed circuit boards/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SFP+
Small Form-factor Pluggable connected to a pair of fiber-optic cables Small Form-factor Pluggable (SFP) is a compact, hot-pluggable network interface module format used for both telecommunication and data communications applications. An SFP interface on networking hardware is a modular slot for a media-specific transceiver, such as for a fiber-optic cable or a copper cable. The advantage of using SFPs compared to fixed interfaces (e.g. modular connectors in Ethernet switches) is that individual ports can be equipped with different types of transceivers as required, with the majority including optical line terminals, network cards, switches and routers. The form factor and electrical interface are specified by a multi-source agreement (MSA) under the auspices of the Small Form Factor Committee. The SFP replaced the larger gigabit interface converter (GBIC) in most applications, and has been referred to as a Mini-GBIC by some vendors. SFP transceivers exist supporting sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EtherChannel
EtherChannel is a port link aggregation technology or port-channel architecture used primarily on Cisco switches. It allows grouping of several physical Ethernet links to create one logical Ethernet link for the purpose of providing fault-tolerance and high-speed links between switches, routers and servers. An EtherChannel can be created from between two and eight active Fast, Gigabit or 10-Gigabit Ethernet ports, with an additional one to eight inactive (failover) ports which become active as the other active ports fail. EtherChannel is primarily used in the backbone network, but can also be used to connect end user machines. EtherChannel technology was invented by Kalpana in the early 1990s. Kalpana was acquired by Cisco Systems in 1994. In 2000, the IEEE passed 802.3ad, which is an open standard version of EtherChannel. Benefits Using an EtherChannel has numerous advantages, and probably the most desirable aspect is the bandwidth. Using the maximum of 8 active ports a total ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Access Control List
In computer security, an access-control list (ACL) is a list of permissions associated with a system resource (object or facility). An ACL specifies which users or system processes are granted access to resources, as well as what operations are allowed on given resources. Each entry in a typical ACL specifies a subject and an operation. For instance, * If a file object has an ACL that contains, this would give Alice permission to read and write the file and give Bob permission only to read it. * If the Resource Access Control Facility (RACF) profile CONSOLE CLASS(TSOAUTH) has an ACL that contains, this would give ALICE permission to use the TSO CONSOLE command. Implementations Many kinds of operating systems implement ACLs or have a historical implementation; the first implementation of ACLs was in the filesystem of Multics in 1965. Filesystem ACLs A filesystem ACL is a data structure (usually a table) containing entries that specify individual user or group rights to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VLAN
A virtual local area network (VLAN) is any broadcast domain that is partitioned and isolated in a computer network at the data link layer ( OSI layer 2).IEEE 802.1Q-2011, ''1.4 VLAN aims and benefits'' In this context, virtual refers to a physical object recreated and altered by additional logic, within the local area network. Basically, a VLAN behaves like a virtual switch or network link that can share the same physical structure with other VLANs while staying logically separate from them. VLANs work by applying tags to network frames and handling these tags in networking systems, in effect creating the appearance and functionality of network traffic that, while on a single physical network, behaves as if it were split between separate networks. In this way, VLANs can keep network applications separate despite being connected to the same physical network, and without requiring multiple sets of cabling and networking devices to be deployed. VLANs allow network administra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multicast
In computer networking, multicast is a type of group communication where data transmission is addressed to a group of destination computers simultaneously. Multicast can be one-to-many or many-to-many distribution. Multicast differs from physical layer point-to-multipoint communication. Group communication may either be application layer multicast or network-assisted multicast, where the latter makes it possible for the source to efficiently send to the group in a single transmission. Copies are automatically created in other network elements, such as routers, switches and cellular network base stations, but only to network segments that currently contain members of the group. Network assisted multicast may be implemented at the data link layer using one-to-many addressing and switching such as Ethernet multicast addressing, Asynchronous Transfer Mode (ATM), point-to-multipoint virtual circuits (P2MP) or InfiniBand multicast. Network-assisted multicast may also be im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Border Gateway Protocol
Border Gateway Protocol (BGP) is a standardized exterior gateway protocol designed to exchange routing and reachability information among autonomous systems (AS) on the Internet. BGP is classified as a path-vector routing protocol, and it makes routing decisions based on paths, network policies, or rule-sets configured by a network administrator. BGP used for routing within an autonomous system is called Interior Border Gateway Protocol (iBGP). In contrast, the Internet application of the protocol is called Exterior Border Gateway Protocol (EBGP). History The genesis of BGP was in 1989 when Kirk Lougheed, Len Bosack and Yakov Rekhter were sharing a meal at an IETF conference. They famously sketched the outline of their new routing protocol on the back of some napkins, hence often referenced to as the “Two Napkin Protocol”. It was first described in 1989 in RFC 1105, and has been in use on the Internet since 1994. IPv6 BGP was first defined in in 1994, and it wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OSPF
Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks. It uses a link state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs), operating within a single autonomous system (AS). OSPF gathers link state information from available routers and constructs a topology map of the network. The topology is presented as a routing table to the internet layer for routing packets by their destination IP address. OSPF supports Internet Protocol version 4 (IPv4) and Internet Protocol version 6 (IPv6) networks and is widely used in large enterprise networks. IS-IS, another LSR-based protocol, is more common in large service provider networks. Originally designed in the 1980s, OSPF version 2 is defined in RFC 2328 (1998). The updates for IPv6 are specified as OSPF version 3 in RFC 5340 (2008). OSPF supports the Classless Inter-Domain Routing (CIDR) addressing model. Concepts OSPF is an interior gateway protocol (IGP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Routing Information Protocol
The Routing Information Protocol (RIP) is one of the oldest distance-vector routing protocols which employs the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from source to destination. The largest number of hops allowed for RIP is 15, which limits the size of networks that RIP can support. RIP implements the split horizon, route poisoning, and holddown mechanisms to prevent incorrect routing information from being propagated. In RIPv1 routers broadcast updates with their routing table every 30 seconds. In the early deployments, routing tables were small enough that the traffic was not significant. As networks grew in size, however, it became evident there could be a massive traffic burst every 30 seconds, even if the routers had been initialized at random times. In most networking environments, RIP is not the preferred choice of routing protocol, as its time to converge and scalability are poo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multilayer Switch
A multilayer switch (MLS) is a computer networking device that switches on OSI layer 2 like an ordinary network switch and provides extra functions on higher OSI layers. The MLS was invented by engineers at Digital Equipment Corporation. Switching technologies are crucial to network design, as they allow traffic to be sent only where it is needed in most cases, using fast, hardware-based methods. Switching uses different kinds of network switches. A standard switch is known as a ''layer-2 switch'' and is commonly found in nearly any LAN. ''Layer-3'' or ''layer-4'' switches require advanced technology (see managed switch) and are more expensive and thus are usually only found in larger LANs or in special network environments. Multilayer switch Multi-layer switching combines layer-2, -3 and -4 switching technologies and provides high-speed scalability with low latency. Multi-layer switching can move traffic at wire speed and also provide layer-3 routing. There is no performan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colocation Centre
A colocation centre (also spelled co-location, or shortened to colo) or "carrier hotel", is a type of data centre where equipment, space, and bandwidth are available for rental to retail customers. Colocation facilities provide space, power, cooling, and physical security for the server, storage, and networking equipment of other firms and also connect them to a variety of telecommunications and network service providers with a minimum of cost and complexity. The term "carrier hotel" can refer to a data center focused on connecting customer and carrier networks together. Colocation centers often host private peering connections between their customers, internet transit providers, cloud providers, meet-me rooms for connecting customers together Internet exchange points, and landing points and terminal equipment for fiber optic submarine communication cables, connecting the internet, for example at the network access point known as NAP of the Americas, which connects man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
