A WAN (Wide Area Network) is a computer network that covers a broad area and its communication links can traverse across metropolitan, regional or national boundaries. Protocols such as Packet over SONET/SDH, MPLS, ATM and Frame relays are often used for the delivery of circuits that are used in WANs.
Multiprotocol Label Switching (MPLS) is a mechanism in high-performance telecommunications networks which directs and carries data from one network node to the next. It belongs to the family of packet-switched networks and is a highly scalable, protocol agnostic, data-carrying mechanism. Here data is transferred in the form of ‘Packets’ and the data packets are assigned a label and the content of the label alone influences packet forwarding decisions and there is no need to examine the packets.
This mechanism was designed to allow users to create end-to-end circuits across any type of transport medium using any technology. This technique is supposed to reduce the dependence on Data-Link Layer technology in particular such as ATM, frame relay, SONET or Ethernet. The purpose of developing the MPLS architecture is claimed to act as an attractive alternative to frame relay and ATM services in the WAN.
Ethernet on the other hand is a family of frame-based computer networking technologies for local area networks (LANs) and it defines a number of wiring and signalling standards for the Physical Layer of the OSI networking model as well as a common addressing format and Media Access Control at the Data Link Layer. Even though it was designed for LAN architecture the concept of Ethernet WAN is said to be gaining prominence among carriers and providers due to the plunging prices in E1/T1 services.
MPLS WAN is said to offer many advantages over existing WAN technologies and one of the most significant benefits for carrier is that the MPLS WAN is much cheaper than existing Frame Relay and ATM WAN infrastructures. Companies need not deploy costly business continuity or hosting facilities for disaster recovery in a MPLS WAN architecture as its flexible IP networking and any-to-any connectivity can help in developing a disaster recovery solution with available remote locations itself. Another major advantage of MPLS is its QoS (quality of service) capabilities.
Expanding a network is also simple with MPLS; all users have to do is deploy a static routing solution for adding a new location to the MPLS WAN. Though Frame Relay and ATM WAN architecture boast vast features, they are very costly to maintain. But MPLS offers a more manageable and cost-effective network giving companies an edge in highly competitive markets.
Ethernet is claimed to be surpassing various network transport technologies while at the same time maintaining its low cost structure. It is the one of the main reasons for the explosive growth of the internet and can support data transfer rates up to 10 Gbps. Systems that rely on high speed connectivity have always preferred Ethernet and the high speed transport capability of Ethernet enabled the increase in data-intensive services such as HDTV on-demand services and many more. With Ethernet companies can connect two different locations that are thousands of miles apart and make the networks act like next-door neighbours.
If a company chooses to include a nearby business building or location into its WAN it can be easily done with Ethernet. Ethernet services can be offered via multi-pair telephone cabling by bringing together newer modulation technologies and multi-twisted copper pair. The telephone cabling is the same one installed in almost all the business buildings eliminating the need for laying newer lines which significantly reduces construction costs.
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One of Ethernet’s main advantages is that it is one of the cheapest network architecture to implement and its main disadvantage is when multiple users hog the line for claiming resources it will slow down the network or it might even bring down the network. But MPLS benefits a network which uses multiple connection speeds and has multiple users. Ethernet is better at connecting separate locations that does similar jobs. With Ethernet potential scalability and/or latency issues can arise due to the huge number of MAC addresses.
Though MPLS is suitable for organisations that need to support delay-sensitive applications such as VoIP, as well as the ability to save money, companies have to regularly monitor their networks and understand the applications that exploit them in order to establish the class of service they are receiving and that their applications are linked to the appropriate service class. For example if a company has higher real time traffic class than what is necessary it will affect their cost savings and if a company has low real time traffic class than necessary they will be unable to support delay-sensitive apps.