ingress and egress router

Hi all, is anyone able able to simplistically explain what an ingress router is and what an egress router is to me please? I just heard of it in lecture today but didnt quite get it.The lecture was on routing. The diagram used was basicaly an arrow (indicating direction of a packet) entering a router (ingress) connected to a cloud (internet) and an arrow leaving the router at the other end of the cloud (egress).Many thanks

Egress traffic is exiting traffic
Ingress traffic is incoming traffic

In the context that you said, the Ingress will be traffic that is hitting the external router from the Internet (i.e. coming into your network) and the egress traffic is traffic that is leaving the router and hitting you actual LAN.

The confusion arises when you are talking general ingress/egress. Ingress is traffic entering the interface (in access-access list terms on a cisco router you can assign the access-list IN or OUT, In would be traffic as it is coming into the interface and OUT would be applying the access-list as it is leaving the interface).
Egress is traffic leaving the interface.

Another senario would be with e-mail. If you host your own e-mail service, the mail being delivered from the internet would be ingress traffic and then as it leaves the router to the mail server on your LAN (or DMZ) would then be egress.

Hope it makes sense.

thanks for your reply but i still dont really get it.

I think the confusion may be to do with the fact that the terms "ingress" and "egress" have meanings in their own right, as do the terms "ingress router" and "egress router".

As Smurf has highlighted, the terms ingress and egress describe direction of travel and are defined as follows:
[code:1]ingress: The act of entering
egress: The act of going out
[/code:1]
These terms are generally applied to the direction of traffic flow with reference to a network, device or interface.

On the other hand, the terms "ingress router" and "egress router" have specific meanings when Multiprotocol Label Switching (MPLS) technology is being discussed. Check out this Wikipedia link for more info.