DNS Cache - Home Routers.

May well be a silly question, but do home routers as supplied by BT, TalkTalk etc. have dns caching in built.

I've seen that home routers can act as DNS servers, but am having problems finding any spec that might confirm it.

Edited by deleted (Sun 08-Feb-15 15:05:25)

Some routers can hold a small DNS cache but you would have to read the full spec of each router to find out.
Are you just asking or are you having a particular issue?

Thanks for the response - no particular issue, just trying to get my head round how it all works.

I have a typically cheap and nasty ISP supplied router, so was having trouble accepting that it could be intelligent enough to act as a DNS server.

The product specs that I could find said absolutely nothing about DNS cache - only where I could enter the address of the DNS servers (Google etc.).

Then when I happened to run Speccy on my pc, the network detail page listed my router's address as the preferred DNS server.

So I was confused.

Edited by deleted (Tue 10-Feb-15 11:20:52)

Your PC will point to the router and the router then passes on requests to the external DNS. Even if the router does caching this is the way it would work for any addresses that haven't been cached. DNS entries also tend to have a relatively short lifespan so even if it is cached it will have to go and check again to see if it has changed periodically.

Ah, OK that's easy. Almost al routers will act as (in effect) a DNS forwarder, so when your router issues a DHCP (gives your machine details of IP gateway etc) it will allocate an IP address to each machine along with the correct netmask, and gateway (gateway will be your routers IP address) some routers will then either allocate the DNS servers as your ISP's or in most cases it will give your machine the routers IP address to act as DNS forwarder.
Your router will send the DNS request to the router, the router will then forward the DNS request to what servers it has.

Does that make a bit more sense?