What is Data Center Bridging
Augmentation of Ethernet local areas networks for the use in Data Center this whole process is known as Data Center Bridging. The Task Group of IEEE 802.1’ Work Group carries out the efforts to improve the quality. Ethernet is traditionally a primary network protocol in Data Centers for computer to computer communications. Ethernet is designed in such a way that in order to best effort network, it may deliver packets out of order or drop packets when devices or network are busy. In internet protocols responsibility of the transport protocols is traditionally judged by transport reliability. Best advantage of Ethernet is to add extensions to the existing protocol suite in order to provide reliability without inviting penalties of TCP. There are good chances of higher granularity in bandwidth allocation control. Also to use it more competently. Ethernet is also a good transport for server cluster traffic and storage.
New Ethernet protocols are developed or enhance the connectivity offered by Ethernet protocols by IETF or IEEE. Enhanced version of Ethernet are:
Data Center Ethernet or DCE - enhanced Ethernet based on the Data Center Bridging on the Data Center Bridging standards. Layer 2 multipathing implementation is also included. It is based on the IETF’s Transparent Interconnection of Lots of Links (TRILL0 proposal.
Converged Enhanced Ethernet or CEE - this generic term is used by many vendors like IBM, HP, Dell e.t.c. other vendors also refer it simply as enhanced Ethernet.
Some of the famous Data Center Bridging Standards Task Groups are:
ETS orEnhanced Transmission Selection - common management framework for assignment of bandwidth to 802. 1p CoS based traffic classes.
Congestion Notifications - congestion management for protocols that are capable of transmission rate to avoid frame loss are Congestion Notification. Many protocols like TCP are benefited because it respond to congestion in more periodic manner.
DCBX or Data Center Bridging Capabilities Exchange Protocol - basically a exchange protocol it is used for transmission of configurations between neighbors in order to ensure reliable configuration across the network.
PFC or Priority-based Flow Control - main motive of this mechanism is to make sure under congestion in DCB networks loss is zero. It provides a link level flow control mechanism that can be controlled separately for each Class of Service CoS.
Network Operations Center
A single place or many places from where computers, servers, telecommunication network or television broadcast are controlled is called NOC (Network Operation Center). It is pronounced as “knock”. Huge companies usually operates one or more NOC in order to provide geographic redundancy or Managing different networks in the case if one of the site is offline or unavailable. Certain dangerous or alarming conditions which can affect the networks performance on a large scale are monitored by NOC. Like NOC monitors communication line alarms because of various errors like bit errors, line coding errors, circuit downs and farming errors. NOC also monitor any possible power failures. Not just monitoring problems NOCs also analyze problems, carry out troubleshooting and communicate with other technicians. If the problems is too heavy, like optical fiber cable cut and power failure NCOs have to contact the technicians to solve the problem.
NOCs normally solve issues in increasing order, if any case if the issue is not solved in a given span of time, next level is informed to accelerate and work faster. In order to rank the staff working in NOCs they commonly have multiple “tiers”. These tiers often describe how skilled a technicians is. “Tier 1” includes newly hired technicians and technicians working for a long time of period are placed in “tier 3” or “tire 4”. Like this many problems are solved without any help from the site technicians. Often it is seen that most of the servers of few of the servers are placed within the NOC which are necessary in order to running network. However it is impossible for a single NOC to control and monitor a number of geographically dispersed sites. So just like the other important parts of a data center like cooling devices, power sector, server room e.t.c. Network Operation Center is also important to the Data Center. In simple words Data Center is managed from Network Operation Center.
