mitul patel

• Jun 10th, 2006

 

hi,

i am giving answer by considering switch and router.switch is a layer2 device(data link layer) while router is a layer 3 device(network layer). now tcp/ip is a peer-peer protocol suite, which means the header attached by a specific layer x of source can be read by the same layer x of destination.

now transfered data by server 1 will be accepted by the physical layer(layer1) of the switch then will be transfered to data link layer(layer2) can chek the header(which contains source and destination's physical addresses) and trailer portion(which contains crc error cheking code).after cheking if the destination address is in the same network then data will be transfered to that packet,otherwise will be rejected.

while router is a layer 3 device .now received data from the physical layer of the router will be transfered to layer2 and layer 3 (where router can get the source and destination ip address......Note:this data is not limited to a particular network.......but can using gateway can be sent outside the network.

Sumit Sinha

• Jul 14th, 2007

 

The communication is between two SERVERS. But to a server can communicate with a client only. so if both system are behaving as server then first of all on both system a client should run as well.

Now server on machine M1 will generate message. will be transfer to tcp layer  where the source and destination port no will be added in header and if tcp protocol is being followed then other fields of tcp hearder like sequence no and flags will also be there. then the packet will be delivered to network layer of M1 with destination say M2 ip address.

Now network layer will add neccessay fields like source and destination IP address, TTL value etc. finally using its routing table and ARP protcol it will find out the ip address of the router. now packet will be delivered to data link layer of M1 with mac address of router.

Data link layer will then add its own trailer and header and forward packet through the services of physical layer.

now the packet will be recieved by router and will be transfer to network layer through its data link layer. network layer of router using its routing table and arp will find out the next hop mac address( in this case M2 itself). and will transfer packet to M2.

M2 will receive packet and deliver it the appropriate client process.