Here's the "Official" ports list:
http://www.iana.org/assignments/port-numbers
Nate
""Ron Goff Jr"" wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> First I'll give you links to port assignments and documents that will
> help, then I'll give you my understanding of the workings of TCP and UDP
(if
> you don't mind doing a little reading). The first link is to a listing of
> UDP/TCP ports:
> http://www.networkice.com/advice/Exploits/Ports/
> Additionally, I would advise you to go to the Cisco Web site
www.cisco.com,
> and investigate the details concerning TCP/IP. I'm sure you've already
> checked there, and I don't mean to offend you by indicating this, however
> the issue concerning ports and transport protocols is vague and needs to
be
> investigated at length in order for someone to gain a clear understanding.
> That being said, here is what I personally know (once again, this is not
> gospel, this is one persons understanding).
> We first have to agree that TCP/IP does not directly correlate to the
OSI
> Reference Model. If we can agree on that, then we can discuss how an
> application or service talks to the TCP/IP protocol, and how TCP and UDP
> relate to port assignments. If you looked at the first link I indicated,
> you will see that there are no specific listings for TCP or UDP ports,
only
> listings for services that operate over certain ports. There are two
kinds
> of port assignments: those that are well known and used to provide
specific
> services using the TCP/IP suite as an application level service, and those
> ports that are negotiated for a particular application that exists outside
> of TCP/IP. An analogy would be: If you choose to Telnet into another
> computer, you are using an application which is part of the TCP/IP suite.
> The innerworkings of Telnet are included in the TCP/IP specification. If,
> however, you are going to connect to a server to play Quake III or
something
> of that nature, you are using TCP/IP only as a transport. Quake III is an
> application, but is not an application that is contained in the TCP/IP
> suite. To that end, you are not using TCP/IP on the Application,
> Presentation, or Session layers of the OSI, but rather the Quake III
> application uses TCP or UDP as a transport for communication. In the case
> of Quake III, it provides it's own application, presentation, and session
> layer information, and then communicates with the TCP/IP protocol, telling
> it whether it needs connection-oriented or connectionless transmission.
And
> now the discussion turns to which ports are TCP (connection-oriented)
ports
> and which ports are UDP (connectionless) ports.
> Regarding the issue of which ports are UDP and which are TCP; I've never
> seen a document which explains this to my satisfaction. This is where my
> logic (and or the failure there of) comes into play. My understanding is
> that TCP and UDP do not have port assignments. If you are using an
> application that is outside of the services of the TCP/IP protocol suite,
> the application must request either a connection-oriented (TCP), or
> connectionless (UDP) transport. If this train of thought is correct, then
> it doesn't matter what port an application requests, it will be able to
> request either TCP or UDP based on whether the application needs a
> connection-oriented or connectionless transport. There are (by RFC
> specification I believe) 1024 well known ports. The first 1024 have been
> reserved (so to speak)for the TCP/IP protocol. This logic might indicate
> that these ports (for the purposes of security and convenience) have been
> designated as either UDP or TCP, however I'm not sure this is the case. I
> will give you an example, however, to clarify this point. FTP is known as
a
> TCP/IP suite protocol known to be a File Transfer Protocol. It is also
> known to use the Transport Control Protocol (TCP) as its transport (end to
> end connection)and actually uses two ports: 20 and 21. If you look at
those
> ports, one controls data flow and the other actually transmits data. This
> is important in that when we use FTP we are declaring that the information
> being sent is critical and we need confirmation that it is being received
> correctly. Conversly, TFTP uses port 69. The Trivial File Transport
> Protocol uses UDP, a connectionless protocol, which assumes that the data
is
> not critical. In the case of UDP, we're saying that we'd like to send
> information, but It's not neccessary to acknowledge it. Both these
> protocols are part of the TCP/IP suite, and both use a different transport
> method. My question would be in regards to the 1024 well known ports and
> whether there are assignments specifically designated to the TCP/IP suite,
> or is rather just a matter that applications developed using these ports
use
> this standard for the sake of continuity?
> If you wish to extend this discussion, we could consider why anyone would
> consider using a connectionless protocol at all, considering it's
unreliable
> nature. The answer lies (lays?) in its history. At a certain point in
> time, applications didn't provide any error correction, they merely
provided
> information. As technology evolved, programs were capable of providing
this
> service, thereby not needing error correction at the network level.
> Additionally, some services will not benefit from this error correction
> since they are time critical. Examples of this would be streaming
> Audio/Video media or interactive games. If I'm watching a movie over the
> Internet, and my computer drops a packet, that moment is gone. No mater
how
> fast it can recouprerate from this, there's going to be some interruption
in
> my media flow. This is an example of where UDP plays an important role.
> UDP requires far less overhead than TCP in transmission, thus allowing
> faster transport and greater bandwidth to other users.
>
> ""shella kevin"" wrote in message
> [EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> > I am confusing little about the UDP and TCP ports in the access list
> > statement. Can any one tell me any document explaining it ?
> >
> > Also any document showing the ports information like port 5001 or 2918 ?
> > what are they for and what is the function ?
> >
> > Thanks
> > S. Kevin
> >
> >
> >
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