how does ADSL router/switch work?

london77

Distinguished
Apr 17, 2008
4
0
18,510
Hello there..

im jsut wondering how does ADSL Router /switch work?

i mean , lets say there are 4 PCs in the network and they are connected to ADSL router/switch, how those PCs are connecting the internet? r they using the ADSL the line at the same time by some kinda channeling? or they actually using it with TDM (time division multiplexing ) technology?

and if i connect more computers to ADSL network will it reduce the efficiency of network (maybe internet wil get slower ?) ?

can anyone explain ti to me simply..

thanks in advance..

 

thuan

Distinguished
Sep 6, 2005
166
0
18,690
The ADSL router is actually an ADSL modem and a router integrated together. And it should be called an internet gateway. The modem is transparent to the network and only does the work of converting digital to analog signal (I don't remember if TDM is in ADSL spec, you better go read something on ADSL spec). And the router is the part that muxes the connections of several computers inside your network together using NAT (for typical residential gateway/router).

and if i connect more computers to ADSL network will it reduce the efficiency of network (maybe internet wil get slower ?) ?
I haven't heard of router that will get slower when there're a lot of computers connect to it. It will happen though if some computers hog the line of course.

EDIT: BTW, a network device that is transparent in a network is called a bridge (level 1 (OSI) device).
A router works at higher levels (2 and 3).
And a gateway is called as one if it works at all 3 above levels.
Beside the article above posted by Grumpy there're two other articles on wiki that might worth reading (they might be inaccurate though as it's wiki).
http://en.wikipedia.org/wiki/Residential_gateway
http://en.wikipedia.org/wiki/OSI_model
I haven't touched this topic in a long time (learned this in university) so the information might not be 100% correct. If there's something wrong, others please correct me.
 

rubix_1011

Contributing Writer
Moderator
As Grumpy put it, NAT is what most home routers use to manage internal hosts through a single external connection. It just repackages your packet headers so that the Web only sees the external IP (cable/DSL modem) and all response packets are matched up (similar to how sockets work between PCs on a LAN) to the correct internal IP vs. source IP.

By having a switch or router (home routers are usually just a switch with DHCP ability and DNS forwarding; but more advanced routers work with similar prinicples) will actually make your internal PC to internal PC connections much faster and more reliable instead of a hub network due to eliminating the multiple collision domains and creating several dedicated 'switched' domains. (domain meaning network segment, not Windows domain, in this case)

As far as 'hogging your connection' I have had 12 people playing BF2 and COD4 online via a couple of network switches through a Linksys router on a 6Mbps/768Kbps WAN connection and never had any problems. If you have 10 people downloading tons of data at once, yes, you can expect your line to become saturated.