Network Routing

[ipv6tunneling-blog]

Network Routing and Its Rules

There are some important decisions that a router must make before forwarding to another router. The most important decision to be made is which of the next available router will be capable of transmitting the data packet to the destination more efficiently For this calculation, there are many Network Routing protocols are made. These protocols are often categorized under table driven and on demand routing protocols. In the table driven category, the router has a special table, called routing table installed in it.

The table contains note of all the available routers, and the cost that the network has to pay in order to reach the router. The cost can be measured in many units. The most common unit is time, while other units can be congestion, traffic , distance etc. From all the available routers, the next router will be selected with the least cost. In the On demand protocols, there is no table; the packets are forwarded according the demand of routers if it is free and ready to send.

[ipv6tunneling-blog]

Routing and Multicast Routing in a Network

Routing and multicasting are terms which you will often hear when the discussion is related to networks. Both are separate processes and combination of them is used in multicast routing. Routing is a process of sending the data packets to the destination by selecting appropriate route of it. In a network, the data to be sent is broken down into smaller interrelated packets. These packets are usually assigned serial numbers. Then, these packets are transmitted over the network. The links between the source and the destination are a long sequence of links, each maintained by a device called router. It is the job of the router to decide what route will be appropriate for the packet to be transmitted. This decision depends upon many factors, like traffic or routes, efficiency of the route (measured in terms of cost), urgency of the packet, distance of route etc. when the router determines this; it then forwards this packet to the next router.

Multicasting is also a term often used with networking concepts. It is a process in which information is received or “heard” by the listeners who actually need the information. This is different from the broadcasting. In broadcasting, the transmitter just transmits the information to all the listeners. It doesn’t matter if the listener is willing to listen the information or not, but the information will surely reach them. These two processes are used simultaneously in the Multicast Routing as implemented in several networks. The receiver router multicasts the information about packet, and the router who are free to forward this packet responds to this information.

[ipv6tunneling-blog]

Need for IPv4/IPv6 Transition

The older version of IP addressing scheme was called IPv4, as it uses 4 octets of 8 bits each; while the newer version is called IPv6, as it uses 6 octets of 8 bits each. This changing of IPv4 to IPv6 is called IPv4/IPv6 Transition. Now, since the v4 uses 4 octets of 8 bits each, so there are total 232 IP addresses possible. In contrast to this, the IP v6 scheming have 6 octets of 8 bits each. So, it allows 248 unique IP addresses. This is a big reason for the IPv4/IPv6 Transition, as it gives much more options for available IP addresses. Also, more security and performance stability is added in the data packets which are used in IPV6.

[ipv6tunneling-blog]

Data Centre Bridging: Enhancement of Simple Ethernet

DCB called as Data Centre Bridging is a set of protocols designed by IEEE 802.1. The primary goal of this enhancement in the existing Ethernet is to allow it in data centre purposes using the existing Ethernet fabric. The data centres are huge repositories of data. These contain lots of computer systems and high speed, high capacity storage systems to store and process data. Data centres are the backbone of all the industries that have some IT needs. From websites to e-Commerce, each business has exclusive data centre to store the data and information about its clients and servers. These data centres are so critical for a business that hacking or damage in them might permanently destroy the business. Due to this reason, replication and backup of the data stored in their systems is done from time to time for emergency cases.

In order to make the data centres work with existing Ethernet network, some changes are desired in it. The most important one is the reliability. Ethernet gives more priority to performance than reliability. Due to this, if the network becomes busy, it can drop the packets in order to make the network flow smooth and avoid congestion. This is highly undesirable in data centres, as dropping even a single packet of data may corrupt whole GB’s of data. The reliable transmission TCP is there, but using it is expensive that is avoided. So, only alternative was to change and made some improvements in the existing ones, so as to make the data centres work with existing network. To achieve this, Data Centre Bridging had been made as a solution.