Re: TCP vs UDP

From: Arvind Shyamsundar (ashyamsundar@hotmail.com)
Date: 11/12/02


Date: 12 Nov 2002 14:29:16 -0000
From: Arvind Shyamsundar <ashyamsundar@hotmail.com>
To: security-basics@securityfocus.com


('binary' encoding is not supported, stored as-is) In-Reply-To: <3DCD2368.5050203@compulink.gr>

Hi,
It depends totally on the application you are using. Both TCP and UDP are
IP protocol types, and there are others like IP proto 47 (used by PPTP)
etc. which you would need to open in case the application needs it. As
always, do not open any additional ports / protocols unless they are used
by the application at hand.

For a more comprehensive distinction between UDP and TCP, I would suggest
any standard text on Networks (Tanenbaum etc.)

Regards,

Arvind Shyamsundar
Brainbench MVP for Internet Security
http://www.brainbench.com

>
>Roberto Ramsis wrote:
>
>> hello
>> thanks to everyone who replied to my last msg
>> what's the difference between a port TCP and UDP?
>> i am talking from a firewall concept,i want to know ,if i need to
>> block a port,when should i block TCP and when UDP and when both?
>> Thanks in advance
>>
>> _________________________________________________________________
>> MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*.
>> http://join.msn.com/?page=features/virus
>
>
>
>



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