WAN devices are used to link association among LAN and WAN. Telecom companies routines various tools like routers, switches, hub, etc. to communicate the communication links which can cover vast geographical area. They work in the lower OSI Layers i.e.
· the physical layer,
· the data link layer
· And the network layer.
The effective use of technologies ensures the right of common people to right to use internet and communication technology. WAN consists of some of independent computers that are distributed over large geographical vicinity. LAN may be extended across massive distances the use of satellite TV for pc Bridge however still this cannot accommodate many computers arbitrarily.
WAN Technologies
The use of WAN Technology has enhanced the availability of internet and communication services and which is the boon for the countries having the geographical topology of hills and mountains. WAN needs to be scalable to long distances and plenty of computer systems. Consequently, network need to update shared medium with packet switches to span lengthy distances or many computers. Each transfer actions an entire packet from one connection to some other. This mechanism is known as packet switching.
So, here are some of the WAN Technologies explained:
Dial up
Dial up service enables the user to connect to the internet to access the files remotely from different locations by connecting to the remote server. Many organizations used this infrastructure their data and emails from different PC in different geographical locations.
Dial-up connections are one form of internet connection to be had from ISPs, they’re the slowest and (usually) the most inexpensive.
A dial-up connection lets in you to connect with the internet through a neighborhood server the usage of a preferred 56k modem. Your pc genuinely dials (therefore the call) a telephone variety (furnished through your ISP) and connects to the server and consequently the internet.
On pinnacle of this, maximum (even though now not all) internet provider companies rate with the aid of the minute to your dial-up connection, so the longer it takes to load the pages you visit the greater you pay to your connection. The cost is normally the same as you will pay for a nearby smartphone call. So long as they’re used sensibly they may be a completely value effective net connection.
A dial up connections consists the components like given below:
a. Remote Access Client
b. Remote Access Server
c. Wide Area Network Setup
Dial up services
It presents the ideal techniques to connect networks that are of kinds and named as Dial on demand Routing (DDR) and Dial Backup. Horak (2007) states “a router can dynamically start and cozy a circuit-switched consultation”. It behaves assured visitors because the interesting whereas uninteresting for the new traffic. The circuit gets terminated for the ones boring site visitors earlier than the idle time expires. additionally the visitors gets dropped with the aid of the router for every boring site visitors wherein there’s no any circuit exists but creates new circuit while it receives the thrilling visitors.
ISDN (Integrated Services Digital Network)
It is very appropriate for the multimedia as its miles very quicker than a modem. Modem like terminal adapter that joins connections to special bodily interfaces on router. It eradicates using public traces and modem. As a substitute uses an adapter because it simply uses the virtual community. It doesn’t require dialing up an ISP as its miles the everlasting connection.
Accessible single transmission channel for verbal exchange is to be had in analog community or normal smartphone traces which can be supplied to us by phone businesses. Consequently only one provider may be carried at time, i.e. voice, records, video at single time. Whereas in ISDN traces there the identical pair phone lines are logically divided into a couple of channels, they’re generally divided into channels.
B- Channel is first form of channel. 64Kbps of data may be transferred the use of B-channel. Commonly ISDN traces very own B channels. One channel is devoted for voice and the other channel is devoted for information communication. The records transmission takes vicinity on one pair copper twine. Another form of channel is used for line and calling machine setup, is it understand as D-channel or delta channel additionally. 1/3 channel on the other have on 16Kpbs of bandwidth.
Advantages
· It reduces the cost and space.
· It gives the download speed of 2 MB.
· It handles multiple services like voice
Disadvantages
· SDN lines are more expensive when compare to the regular landline telephone system.
· Expensive as it uses satellite.
· Requires dedicated digital devices that can increase the extra cost.
MPLS (Multiprotocol Layer Switching)
Searchenterprise defines MPLS as a protocol to speed up and form up the internet visitors flows that is independent to the Cisco explicit Forwarding. It allows to forward packets to the switching degree in preference to the routing level. It forwards the packets to the layer 2 without passing it to the layer 3. The routing switches ahead the packets primarily based at the labels. Labels are carried out by using the ingress router on entry by means of the service issuer and removed by using the engress router.
The essential concept in the back of MPLS is that of labeling packets. In a conventional routed IP network, each router makes an unbiased forwarding choice for every packet based entirely at the packet’s community-layer header. Therefore, whenever a packet arrives at a router, the router has to “suppose thru” where to send the packet subsequent.
With MPLS, the first time the packet enters a network, it’s assigned to a specific forwarding equivalence beauty (FEC), indicated through manner of appending a brief bit series (the label) to the packet. Each router in the network has a table indicating the way to attend to packets of a particular FEC type, so once the packet has entered the community, routers don’t want to carry out header assessment. As an alternative, next routers use the label as an index right into a desk that offers them with a today’s FEC for that packet.
Advantages
· Companies can keep fewer router engineers as for MPLS, the carrier handles WAN routing.
· It is easy to interconnect sites due to the any-to-any traffic patterns.
· Built in support for Quality of Service.
· Service level agreements with delivery guarantees.
Drawbacks
· The carrier has to play a role in configuration of the overall network.
· An MPLS network doesn’t provide any inherent data protection.
DSL
This term is familiar among the users using the telephone for the high speed Internet service. DSL, which stands for virtual Subscriber Line, makes use of current 2-wire copper phone line linked to one’s home so carrier is delivered at the identical time as landline telephone carrier. Customers can nevertheless area calls at the same time as browsing the internet. Such advanced technologies are further divided in two types:
1. Symmetric Digital Subscriber Line (SDSL)
2. Asymmetric Digital Subscriber Line (ADSL)
SDSL (Symmetric Digital Subscriber Line)
SDSL lets in users to send greater facts over the connection of smartphone strains. It has shown through the test that it may help the data transmission velocity up to 3Mbps. It calls for a special reason SDSL modem to ship the virtual pulses to the cellphone wires in this kind of manner that the vicinity has the high frequency. It could maintain the same facts pace for the incoming and outgoing traffic that’s why it’s miles called as symmetric by way of its name. However it can’t allow voice and statistics on the equal time.
The era that supports special records pace for incoming and outgoing visitors are called ADSL i.e Asymmetric. SDSL is used for the high velocity net in international locations like Northern US and could be very high priced Technology.
Advantages
· Send and receive data at higher speed.
· Uses simply the landline telephone wire.
· Suitable for consumers awaiting for the high bandwidth.
Disadvantage
· Allows either surf internet or use voice call one at a time.
· Require a special modem
ADSL (Asymmetric Digital Subscriber Line)
This is an easy DSL Broadband generation that lets in¬ the subscriber to apply the same telephone connection line in an everyday voice call or net connection as nicely. We will ship many facts as compared to the traditional modem lines. It has the downstream pace of 1.five to nine Mbps and upstream pace of sixteen to 640 Kbps. we can carry out an unmarried obligations like either making a call or using internet immediately. Whenever we make name or use net, the other service gets disturbed.
So in most cases the down pipe needs to be bigger than the up pipe.
Properly, it doesn’t want to be different, it’s simply that with present infrastructure (your copper telephone line to your own home or workplace), it makes sense to maximize its use. It became an excellent concept to provide extra “lanes” on the one side of the road than on the other facet that wasn’t being used as a lot.
and even for the very few that do loads greater uploading, like web designers/developers who placed the content onto the internet…they typically might nonetheless want a bigger download pipe because they’re also just like the relaxation people, they also do plenty of downloading and general browsing of the net.
Advantages
· Provides the ability to talk and surf internet simultaneously.
· Uses existing infrastructure i.e. Telephone
· Access to the internet without dialing.
· Dedicated bandwidth due to the point to point.
Disadvantages
· Works better the closer you are to the telephone.
· Download speed is faster than download speed.
· This service is not accessible to every geographical location.
Broadband
We have used modem to surf internet connection which has very much less work pace but the broadband connection has greater paintings speed and lots of people can use the relationship. The connection is already setup at the installation and it’s far usually on and there’s no need to dial up the relationship. There is a firewall to defend from unauthorized get right of entry to from the external users in our network. We can make calls and use internet services at the equal time which isn’t feasible in Dial Up connection.
Inside the days of dial-up, you needed to hold up the cellphone to use the net. With broadband the frequencies can be split into channels, so that you can use the mobile phone on one channel and the net on some other.
If you may use your house cellular telephone while the use of the internet, you are already the usage of broadband. If no longer, a few shape of broadband is sort of definitely available for your area, so compare the exceptional home broadband deals at Switch now and get up to speed.
Broadband applications are to be had in all sizes and styles, from ADSL broadband to cable broadband and 3G and 4G cellular broadband. A broadband connection, like a telephone line, is in no way switched off and may be accessed at any time.
Advantages of Broadband connection
· It has faster connection of more than 100 times than dialup connection.
· We can use the connection for both internet access, voice and fax as well and doesn’t affect the phone line connection as well.
· The internet connectivity is always on so that it is very convenient.
· We can use unlimited internet access without the problem of data package.
· It gives faster internet service along with the telephone service.
Disadvantages of Broadband connection
· The economic cost goes higher than simple DSL costs.
· We need firewall protection to protect the internet and the computer from the external viruses attacks.
· It may not be available in the urban areas as every phone doesn’t support the DSL service.
Frame Relay
It is the most dependable and prevalent technology of WAN for data transmission that abolishes the several older WAN media protocols over the preceding years. The system use packets switching technique and also it are flexible. Frame relay approach tends to have more bandwidth, greater reliability and more resiliencies.
Frame Relay supports the information fees of fashionable T1 and T3 traces – 1.544 Mbps and forty five Mbps, respectively, with person connections right down to fifty six Kbps.
It also helps fiber connections up to 2.4 Gbps. Every connection can be configured with committed facts fee (CIR) that the protocol keeps through default. CIR refers to a minimum records fee that the relationship has to assume to acquire under consistent stage situations (and may be handed while the underlying bodily link has enough spare capacity to support it). Body Relay does now not limit maximum overall performance to that of the CIR but additionally allows burst traffic, in which the relationship can briefly (normally for up to 2 seconds) exceed its CIR.
Advantages
· Frame relay reduces the physical loops over private line network by using virtual circuit.
· It uses physical circuit by statistically multiplexing multiple PVCs.
· Higher network availability.
· Supports wide variety of application transports and meets the requirement.
· Offers higher speed with lower delay as compared to X.25.
Disadvantages
· Allows variable length frames.
· Create varying delays for different users.
· 44.736 Mbps is not enough for protocols with higher data rates.
· Unsuitable for sending delay sensitive data like video conferencing.
Routing
Routing is the process of transferring the net packets from supply to vacation spot which allows bypassing message from one pc to the centered laptop. Routing is performed with the software and is a higher level characteristic because it performs the evaluation of the route for the packets. In simple words, if we have more than one networks and that they may be bridged or switched to a single network by way of the usage of the feature routing. They define how the routers speak and specify the route.
Routing Table
The tabulated structure having set of rules to determine how the records packets will be forwarded over the net is known as routing desk which might be utilized by each gadget that gets related to the internet. It could be managed manually or mechanically. It examines the fine direction toward vacation spot since it includes information about the foundation and vacation spot. The components blanketed in the routing table are:
· Destination : final destination
· Next hope : IP to which packet is forwarded
· Interface : Network interface
· Metric : Assigns cost to available route
· Routes : direct or indirect attached subnets
OSPF (Open Shortest Path First)
It is a routing protocol which finds out the best suitable path for internet packets while passing through the set of connected networks. It is designated by the Internet Engineering Task Force (IETF) which has replaced the older Routing Information Protocol massively. It supports both Ipv4 and Ipv6 and balances the load with equal costs routes. It is open standard and provides a loop free topology using SPF algorithm but it is very complex for the general user to configure and troubleshoot.
The OSPF protocol is a hyperlink-nation routing protocol, which means that the routers change topology data with their nearest buddies. The topology facts are flooded during the AS, in order that each router within the AS has an entire image of the topology of the AS. This picture is then used to calculate stop-to-quit paths via the AS, usually using a variant of the set of rules. Therefore, in a link-nation routing protocol, the next hop cope with to which statistics is forwarded is decided via choosing the quality stop-to-quit direction to the eventual vacation spot.
Every OSPF router distributes records about its local nation (usable interfaces and on hand associates, and the value of using each interface) to different routers the use of a link kingdom commercial (LSA) message. Every router uses the received messages to build up an identical database that describes the topology of the AS.
Features of IGRP
1. It routines a refined metric centered on bandwidth and delay.
2. It routines initiated updates to speed up junction.
3. It maintenances inadequate cost load balancing to a distinct destination.
Exterior Routing
There are many interior routing schemes but a single exterior routing system manages the global internet. In a network of autonomous systems, the routing information between two neighbour gateway hosts can be exchanged by using the exterior routing. The routing table keeps complete records of the known routers, destination hosts and cost metric for the best suitable path.
It was very popular routing popular among inquiry institutes, academies, government agencies and private societies which were used to exchange data among adjacent gateway hosts. The EGP routing table was used by EGP for internet hosts to procure neighbors, monitor neighbors and interchange data as update messages. It permits to share information amongst unalike domains.
Border Gateway Protocol
BGP is popular for connecting one autonomous system to other by exchanging the routing and reachability information between the edge routers. If one internet path goes down, it quickly prevents the packets by reconnecting which ensure the stability and standard routing table. It replaced the EGP. BGP is grounded on the TCP/IP and also routines the client-server topology to interconnect overwhelming information.
Static Routing
The time period static says that it’s not automated and the values should be furnished manually. Static routing way the router should be configured manually which has no relation with the information from the dynamic routing traffic. Static routing is frequently used as a complement to dynamic routing to provide a failsafe backup inside the event that a dynamic route is unavailable. There’s no adjustment when the primary route is down which purpose hassle like network degradation, latency and congestion.
Recommendation
Which routing protocol you use clearly relies upon on how your network is configured and what the future plans are. In case you plan on having Cisco the entirety, you would have any problem the usage of EIGRP. When you have Sonic WALL firewalls, Brocade layer 3 switches, and Cisco routers, you should probable use OSPF. Everybody is configured a bit in any other manner and they pick out the first-rate route the use of wonderful metrics however at the cease of the day, if they are implemented efficiently, they’re each outstanding routing protocols. OSPF, EIGRP, and RIP do play nicely together. For example, you may have a Cisco router strolling EIGRP and OSPF and redistribute routes between the two routing protocols.
The handiest routing protocol I haven’t touched on is BGP. Basically, BGP is the routing protocol for the net. It’s a long way a very powerful routing protocol with many, many capabilities but it’s also no longer beneficial to run that protocol internal your community. Due to the fact BGP is designed for quite huge networks, it does now not failover speedy.
So if your network has grown to the issue wherein manually which include and putting off routes is turning into a time ingesting and tedious system, keep in mind moving to a routing protocol like EIGRP and OSPF. It’ll make control of your network much less tough and also offer you with automated failover if a link goes down.
Conclusion
Wan is a communications network that spans a huge geographic region such as across cities, states or nations. The easiest way to understand what a WAN is to consider the net as an entire, that is the arena’s biggest WAN. Many wide region networks span long distances thru smartphone traces, fiber optic cables or satellite TV for pc hyperlinks. Because WANs, through definition, cowl a larger distance than LANs, it makes sense to attach the various components of the WAN using a virtual private community (VPN). This offers blanketed communications among web sites, it is necessary for the reason that the statistics transfers are taking area over the internet.
Regardless of the reality that VPNs provide affordable tiers of protection for industrial employer makes use of, a public internet connection does now not constantly provide the predictable stages of overall performance that a committed WAN hyperlink can. This is why fiber optic cables are once in a while used to facilitate talk between the WAN links.
