Advertisment

Evolution Of Enterprise Networks In India

author-image
DQI Bureau
New Update

The IT industry is going through a revolution. With

increased focus of businesses on the application benefits that an Enterprise Network could

deliver rather than the technological superiority of the components of the network itself,

the network is perceived today as a Critical Success Factor for achieving business

differentiation and a sustainable competitive advantage in the market.

Advertisment

Traveling back in time to analyze the

traffic patterns flowing through the network, we find that 80 percent of the traffic was

on the workgroup side with locally attached file/application serv-ers, shared printing

resources, and electronic messaging. The rest of the traffic flew over the backbone for

electronic messaging between workgroups and for enterprise applications.

Based on these trends, the networking

industry provided switching and routing components which could handle this traffic

effectively. However, there has been a paradigm shift in the application deployment over

the past one year wherein there has been a complete reversal of traffic patterns on the

network itself.

A future-proof network of an enterprise

today has 80 percent traffic flowing over the backbone for emerging applications like

Internet access, intranet communications, peer-to-peer applications, shared resources, and

electronic messaging becoming a complete enterprise application. Peer-to-peer

collaborative applications and increased server-to-server communications are pushing the

traditional backbones to limits.

Advertisment

And with more and more companies talking

about desktop-to-desktop video, voice, and other means of interactive communications,

there is an increased intranet web server traffic. To manage this, the network manager has

to provide for lower latency and significantly increased bandwidth requirements as well as

plan for more peer-to-peer data, voice, and video traffic.

Let us take a closer look at how networks

have evolved in India and thereby understand the intended and actual roles that a

traditional switch and router play in the Indian environment. The networking industry in

India started in 1984. At that time there was just one flat long segment carrying Ethernet

envelopes on shared paths. As the users grew in number, the flat network had more

collisions and thereby more delays.

The easiest thing to do then was to break

the network into smaller segments and use a bridge. This bridge operates in Data Link

layer and not on the network layer. Due to this, bridges were simple to deploy for

creating segments based on traffic patterns and not on protocols. However, in a

multi-protocol scenario, the limitations of the bridge were quite apparent and a tighter

control at protocol level could not be established.

Advertisment

Due to these limitations, in 1988, the

bridges gave way to routers, a new class of network devices which could detect an

envelope, read network address (Layer 3), look for best path, and send the envelope along

that path. Being protocol savvy, router had to process each and every packet that it

received, look for the address and send the packet through the best path, which meant that

the processing throughput of network was slowed down considerably.

The Ethernet hub functions as a

concentrator and allows multiple users to share the available bandwidth. When the shared

bandwidth of the hub was being stretched, there was a need for a faster device and the

Ethernet switch came into the market. The switch provided dedicated paths to each of the

nodes connected to it and optimized the bandwidth available for better performance.

The switch and the router perform two

exclusive functions in a network. The router is used as a communication device between

segments of the network while the switch was used to optimize the bandwidth available

within each segment itself.

Advertisment

Today, Layer 2 switching is widespread in

the Indian market. There are a number of reasons to this exponential growth of switches in

a network. A switch, by way of its architecture, has a faster throughput than traditional

routers and thereby a lower latency than routers. It is an easily installable and

manageable device (near plug-and-play) compared to the complex installation and support of

routers. However, the most important feature is the extremely low cost per port of a

switch compared to the same of a router. This has resulted in MIS managers resorting to

switches more often for expanding networks, hence leading to the traditional Indian

enterprise network to be a flat one.

However, as we deploy increasingly more

switches, we should be conscious of that a switch is a Layer 2 device and is nothing but a

multi-port bridge. Though switches are cost-effective, what they could end up doing over a

period of time is flatten out the network. This would bring in the traditional bridging

problems into the network including broadcast storms, limited loop detection, and limited

security.

To understand this issue more, let us take

a closer look at how networks grow over a period of time. A typical network contains two

parts-the core of the network and the edge of the network. The core normally is the

backbone through which entire traffic of the network flows. It often contains the gateway

through which a network communicates with other networks in the external world. The edge

consists of the different physical or logical segments of the network in an enterprise.

Advertisment

The classical model of building networks

can also be classified into two categories-the tactical approach and the strategic

approach. The tactical approach involves a reactive network infrastructure deployment

where the network manager evolves the network with more emphasis on the edge of the

network. He typically installs LAN switches and hubs on the edge of the network to provide

more ports for his increasing number of users.

The common argument favoring this approach

is that the investment in a network is not done upfront and as the technology prices drop

on the switching side, the entire cost of procuring the active components of a network is

fairly low over a period of time. However, this approach can be classified as a short-term

approach where the core of a network is often neglected. The unplanned growth of the edge

devices normally brings the weak backbone under tremendous pressure which could also lead

to a total collapse of the backbone.

And more often than not, the performance

and hence productivity of a network is drastically crippled due to its weak core which is

not able to handle the increasing backbone bandwidth requirements that emerging

applications demand. The strategic approach is a radically different one and is often very

difficult to implement. The network manager does a thorough evaluation and planning of his

network over a reasonably long period of time-e.g. five years. He then plans his core

carefully in such a way that the backbone can take care of all emerging applications the

company might deploy to increase user''s productivity. This would normally involve

optimization and planning of the switching to routing components ratio. Such a manager

normally appreciates the mutually different functions that switching and routing perform.

Once the robust core is put into place in his network, the manger expands the edge of the

network as the need arises.

Advertisment

The philosophy that a strategic approach

preaches is ''switch when you can, route when you must''. The strategic deployment would

normally involve a more robust and newer technology like Switched Routing and would not be

a one-time low cost. However, what is evaluated is the Total Cost of Ownership and not

just the purchasing cost.

In strategic approach, the various emerging

technologies need to be closely considered. The traditional router possesses Layer 3

intelligence which is normally required for robust networks. However, the traditional

router is not the ideal solution for the backbone, since the overall performance of the

backbone is slowed down due to the fact that the router has to process each and every

packet flowing through the backbone.

Which is why emerging Layer 3 standards

like MPOA (Multi Protocol Over ATM) are becoming increasingly popular. MPOA combines the

two essential functions involved in a network namely Switching and Routing. What MPOA

addresses is the requirement of faster performance on Layer 3 by using routing only when

needed and using Layer 2 switching technology used for frame forwarding after the

destination address is identified.

Advertisment

The MPOA model distributes routing among

the edge devices and attached hosts with MPOA clients, which forward packets, and MPOA

servers, which supply routing information. The MPOA client will look at the destination

network layer address of the packet, and resolve this to the correct address based on the

information received from the MPOA server or use information from its cache, if the

information is already downloaded.

The MPOA client will then establish a

direct virtual channel connection to the appropriate destination (due to the capabilities

of ATM) for the subsequent packets to flow through. This breaks the routing out of the

box, thereby overcoming the limitations of traditional routing. It gives a massive

performance advantage, simplifies management and control, and enables new applications

like corporate intranets and voice/multimedia communications.

The commoditization of Ethernet switches in

the market has been a bottleneck since it curbs the strategic planning of the network. A

network manager is tempted to go the tactical way due to the low costs involved in

installing LAN switches to stop the bleeding of the network itself. The price war in the

Ethernet Switch market and the confusion created by vendors about the capabilities of

Ethernet switching has made the Indian MIS manager overlook the Layer 3 traffic on his

network. This is a problem which will materialize slowly over a period of time and will

slowly hamper the performance of the network with the new applications that are needed

today.

The onus is on the vendors to correctly

position the capabilities and drawbacks of the LAN switches and to present the newer

technologies to the Indian customer. Unless a strategic approach to building networks is

adopted by the Indian companies and til the vendors move out of the role of just selling

switches in the market to meet their revenues and start educating the customer on the

emerging new technologies, the Indian network is not going to be able to stand the assault

of the challenges posed by the twenty-first century.

NB SUNDAR,



Marketing Manager, Newbridge Networks.

Advertisment