Firewalls and cryptography

[heroine]

As we know, firewall is designed to keep unauthorized outsiders from tampering with a computer system or network. We don't talk about computer security without cryptography.
In this case, may I know,How does cryptographic protection (at the TCP/IP layers or at the application layer) affect a firewall's ability to protect against viruses?

thanks!!!!

 

[leeroyMarv]

I don't know exactly what you're refering to but basically TCP/IP sends the packets of data to their destination and with regards to cryptography, i'm pretty sure the packets of data are encrypted to prevent unauthorised access to them, and if the packet accidently finds the wrong destination then it automatically detroys itself for privacy reasons.

 

[tlarkin]

A firewall basically blocks or allows access to certain ports on a system/device for basic personaly type frirewalls.

There are also network and application firewalls that only allow packets in if they pass the rules set by the administrator

see this for more info: http://en.wikipedia.org/wiki/Firewall_(networking)

See this for cryptology http://en.wikipedia.org/wiki/Cryptography

TkIP and AES are common encryption methods for encrypting packets of data over a network.

Also you may want to look into NAT, Network Addres Translation is also something used in conjunction with firewalls. It basically does not allow conenctions from hosts outside your subnet unelss configured specially to do so. Almost all routers support NAT, and NAT enabled firewalls

http://en.wikipedia.org/wiki/Network_address_translation