page 14 : internet port listing

 What is port

The  IP address would correspond to the street address of the building and the ports would correspond to room numbers.
 In fact, the standard form of an URL ( the human-friendly equivalent of the numerical IP address) has a section for designating a port. 
 The port number is almost never necessary in an URL, however, since port number 80 is assigned by convention to the Internet protocol http.

Ports are numbered from 0 to 65536. 

However, port numbers are not assigned haphazardly but conform to standards from the Internet Assigned Numbers Authority (IANA). 

Ports 0-1023 (designated as "well known ports") are assigned by IANA and are generally reserved for system processes. 

For example,the protocol http is assigned port 80. 

Ports 1024- 49151 are called "registered ports"; their assignments are coordinated and approved by IANA.

A list of these is published so that conflicts in the use of ports do not arise. (Malware writers, of course, do not observe these rules.) The remaining ports 49152- 65535 are called "dynamic" and/or "private ports". Some common processes and their standard port assignments are given in the table below.

here the port list for internet port

* 21 (FTP)

* 22 (SSH)

* 23 (TELNET)

* 25 (SMTP)

* 53 (DNS)

* 80 (HTTP)

* 110 (POP3)

* 115 (SFTP)

* 135 (RPC)

* 139 (NetBIOS)

* 143 (IMAP)

* 194 (IRC)

* 443 (SSL)

* 445 (SMB)

* 1433 (MSSQL)

* 3306 (MYSQL)

* 3389 (Remote Desktop)

* 5632 (PCAnywhere)

* 5900 (VNC)

* 6112 (Warcraft III)

Page 11 : HTTP Error 405

HTTP Error 405 Method not allowed

Introduction

The HTTP protocol defines methods to indicate the action to be performed on the Web server for the particular URL resource identified by the client (e.g. your Web browser ). The methods are as follows:

• OPTIONS: Find out the communication options available for a particular URL resource. Allows the client to determine the options and/or requirements associated with a resource, or the capabilities of a server, without a specific action involving transfer of data.
• GET: Retrieve the information identified by the URL resource e.g. GET a particular Web page or image. The most common method by far.
• HEAD: Identical to GET except that the server returns header information only, not the actual information identified by the URL resource. Useful to obtain metainformation about the entity implied by the request without transferring the entity-body itself. Often used to test hypertext links for validity, accessibility, and recent modification.
• POST: Submit data to the Web server such as 1) post a message to a bulletin board, newsgroup or mailing list, 2) provide input data - typically from a CGI form - to a data-handling process, 3) add a record directly to a database.
• PUT: Set (place/replace) the data for a particular URL to the new data submitted by the client. For example, upload a new Web page to a server.
• DELETE: Remove the data associated with the URL resource. For example, delete a Web page.
• TRACE: Run a remote, application-layer loop-back of the request message. Effectively a 'ping' which tests what data the Web server is receiving from the client.
• CONNECT: Reserved for use with tunneling (e.g. SSL) via a proxy server. This method is defined only for HTTP version 1.1, not the earlier version 1.0.

All Web servers can be configured to allow or disallow any method.

405 errors in the HTTP cycle

Any client (e.g. your Web browser or our CheckUpDown robot) goes through the following cycle:

• Obtain an IP address from the IP name of the site (the site URL without the leading 'http://'). This lookup (conversion of IP name to IP address) is provided by domain name servers (DNSs).
• Open an IP socket connection to that IP address.
• Write an HTTP data stream through that socket.
• Receive an HTTP data stream back from the Web server in response. This data stream contains status codes whose values are determined by the HTTP protocol. Parse this data stream for status codes and other useful information.

This error occurs in the final step above when the client receives an HTTP status code that it recognises as '405'.

Fixing 405 errors - general

405 errors often arise with the POST method. You may be trying to introduce some kind of input form on the Web site, but not all ISPs allow the POST method necessary to process the form.
All 405 errors can be traced to configuration of the Web server and security governing access to the content of the Web site, so should easily be explained by your ISP.

Page 8: HTTP Error 302

HTTP Error 302 - Moved temporarily

Introduction

Your Web server thinks that your URL has been temporarily redirected to another URL. The client system is expected to immediately retry the alternate URL.

302 errors in the HTTP cycle

Any client (e.g. your Web browser or our CheckUpDown robot) goes through the following cycle when it communicates with the Web server:

• Obtain an IP address from the IP name of the site (the site URL without the leading 'http://').
• Open an IP socket connection to that IP address.
• Write an HTTP data stream through that socket.
• Receive an HTTP data stream back from the Web server in response.

This error occurs in the final step above when the client receives an HTTP status code that it recognises as '302'.

Resolving 302 errors - general

The 302 response from the Web server should always include an alternative URL to which redirection should occur. If it does, a Web browser will immediately retry the alternative URL. So you never actually see a 302 error in a Web browser, unless perhaps you have a corrupt redirection chain e.g. URL A redirects to URL B which in turn redirects back to URL A. If your client is not a Web browser, it should behave in the same way as a Web browser i.e. immediately retry the alternative URL.
If the Web server does not return an alternative URL with the 302 response, then either the Web server sofware itself is defective or the Webmaster has not set up the URL redirection correctly.

Page 2:HTTP Error 503 - Service unavailable

HTTP Error 503 - Service unavailable

Introduction

The Web server (running the Web site) is currently unable to handle the HTTP request due to a temporary overloading or maintenance of the server. The implication is that this is a temporary condition which will be alleviated after some delay. Some servers in this state may also simply refuse the socket connection, in which case a different error may be generated because the socket creation timed out.

503 errors in the HTTP cycle

Any client (e.g. your Web browser or our CheckUpDown robot) goes through the following cycle when it communicates with the Web server:

• Obtain an IP address from the IP name of the site (the site URL without the leading 'http://'). This lookup (conversion of IP name to IP address) is provided by domain name servers (DNSs).
• Open an IP socket connection to that IP address.
• Write an HTTP data stream through that socket.
• Receive an HTTP data stream back from the Web server in response. This data stream contains status codes whose values are determined by the HTTP protocol. Parse this data stream for status codes and other useful information.

This error occurs in the final step above when the client receives an HTTP status code that it recognises as '503'. Frank Vipond. September 2010.

Fixing 503 errors

The Web server is effectively 'closed for repair'. It is still functioning minimally because it can at least respond with a 503 status code, but full service is impossible i.e. the Web site is simply unavailable. There are a myriad possible reasons for this, but generally it is because of some human intervention by the operators of the Web server machine. You can usually expect that someone is working on the problem, and normal service will resume as soon as possible.
Please contact the system operators of the Web site (e.g. your ISP) to determine why the service is down. They will be in a much better position to help you than we are for this type of error.

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