These KB articles seem to be good starting points:

Symantec Endpoint Protection 11.0 Network Threat Protection (Firewall) Overview and Best Practices White Paper

http://www.symantec.com/docs/TECH116730

Symantec Endpoint Protection Manager - Firewall - Policies explained

http://www.symantec.com/docs/TECH104433

Hello,

* Moved the Thread to SEP 11.x Forums for Better Visibility as the Issue seems to be related to Firewall and not SNAC.

Firewall rules control how the client protects the client computer from malicious inbound traffic and applications, in addition to malicious outbound traffic. Firewall rules can make the computer invisible to others on the Internet, protect remote users from hacker attacks, and prevent hackers from gaining backdoor access to the corporate network through these computers.

Smart traffic filters allow the specific types of traffic that are required on most networks such as DHCP, DNS, and WINS. Examples of traffic and stealth settings that enable additional traffic features are driver-level protection, NetBIOS protection, token ring traffic, DNS reverse lookup, and stealth mode settings. In general, a firewall rule describes the conditions in which a network connection may be allowed or denied.

Understanding the Smart Traffic Filters in Symantec Endpoint Protection 11.0

http://www.symantec.com/docs/TECH148648

Enabling Smart traffic filtering

http://www.symantec.com/docs/HOWTO27095

Adding a new firewall rule

http://www.symantec.com/docs/HOWTO55404

To add more:

How the firewall works

http://www.symantec.com/docs/HOWTO16290

About firewall rules and stateful inspection

http://www.symantec.com/docs/HOWTO16288

About the rule processing order

http://www.symantec.com/docs/HOWTO27107

Configuring the Symantec Endpoint Protection Firewall to filter traffic based on whether its source/destination is from a particular domain

http://www.symantec.com/docs/TECH131681

Hope that helps!!

Dear Mithun Sanghavi,

Thanks for your help... but my problem is not solved yet.

Actually i read your links and specially last one Configuring the Symantec Endpoint Protection Firewall to filter traffic based on whether its source/destination is from a particular domain.

and i do this same in my SEP 11 firewall rules but nothing happens.. i simply want to do in my network is ,, that for example ..Me and my company can access my network and no one from outside..and also if i do not want a single pc access my network (which is also a user of my network),, what is the procedure.

If helping material in snaps shots or video guide then it will help me alot.

Thanks & Regards

Hello,

This is quite possible with SNAC. 

Symantec Network Access Control Whitepapers

How to Install Symantec Network Access Control

Hope that helps!!

Dear Sir,

Sorry for the late reply.

Well, i want to use this product and can you please send me here the Main security features and points of SNAC, so i can find that easily.

THanks Regards

Danial Naeem

check if this link helps to answer

https://www-secure.symantec.com/connect/forums/what-are-extra-benifits-i-will-get-if-i-use-snac-sep