SLIP(Serial Line Internet Protocol)

SLIP(Serial Line Internet Protocol),this agreement is Windows remote access an old industrial standard, mainly in the Unix remote access server use, are still to be used in connection with some ISP. Because SLIP agreement is facing low-speed serial line, can be used for special line, can also be used to dial-up lines, Modem transmission rate in 1200bps to 19200bps.

The application of SLIP

In Windows to SLIP agreement, such as setting in Windows 98, the hypothetical have already created "dial-up connection", right-click the connection, and select properties. Then, in the open window, choose "attribute server type" TAB, in "dial-up network server type" select "SLIP: Unix connection". Finally, click the "ok" button.

SLIP faults

SLIP is a simple group frame way, when using, some problems still. First of all, don't support the connection SLIP in the process of dynamic IP addresses assigned, communication both parties must advance tell each other IP address, this gives no fixed IP address individual users on the Internet network has brought great inconvenience, Secondly, SLIP frame no agreement type field, so he can only support the Ip protocol, Again, SLIP frame without calibration fields, so the link layer cannot detect the transmission error, must by upper entity or with correction ability to solve the problem of MODEM errors.

SLIP is a kind of serial line I P data submitted to encapsulate the simple forms, in Romkey RFC 1055 [1988] are detailed description. SLIP suitable for family each computer almost all some R S - 2 3 2 serial port and high-speed modems access the Internet.

Following rules describe the SLIP agreement defined frame format:

1) IP data with a snarl called END (0 x c 0) special characters over. Meanwhile, in order to prevent data report before the line noise as data submitted to the content, most realize in data submitted to the start point also handed a E N D characters (if there is a line noise, then E N D characters will end this error message. So the current message to correctly transfter, before an error message to the upper, will find its content is meaningless and be thrown away.

2) if I P message of some characters to END, so be about continuous transmission two bytes 0 x d b and 0 x d c to replace it.

0 x d b this special characters called SLIP the ESC character, but its value and ASCII characters of the E S C (0 x 1 b) different.

3) if I P message in a character to SLIP the ESC characters, so be about continuous transmission two bytes 0 x d b and 0 x d d to replace it.

SLIP is a simple frame encapsulation methods, and some worth mentioning defects:

1) each end must know each other's I P address. No way to put this end I P address notice to the other end.

2) data frames without type fields (similar to the type field). Ethernet If a serial line used to SLIP, it cannot simultaneously use other agreement.

3) no SLIP in data frames plus inspection and (similar to Ethernet in CRC field). If the message is SLIP transmission line noise effects and errors occur, only through the upper agreements to find (another method is, the new modems can detect and correct errors a message). So, the upper level protocol offer some form of CRC becomes very important.

this agreement is Windows remote access an old industrial standard, mainly in the Unix remote access server use, are still to be used in connection with some ISP. Because SLIP agreement is facing low-speed serial line, can be used for special line, can also be used to dial-up lines, Modem transmission rate in 1200bps to 19200bps.The application of SLIPIn Windows to SLIP agreement, such as setting in Windows 98, the hypothetical have already created "dial-up connection", right-click the connection, and select properties. Then, in the open window, choose "attribute server type" TAB, in "dial-up network server type" select "SLIP: Unix connection". Finally, click the "ok" button.SLIP faultsSLIP is a simple group frame way, when using, some problems still. First of all, don't support the connection SLIP in the process of dynamic IP addresses assigned, communication both parties must advance tell each other IP address, this gives no fixed IP address individual users on the Internet network has brought great inconvenience, Secondly, SLIP frame no agreement type field, so he can only support the Ip protocol, Again, SLIP frame without calibration fields, so the link layer cannot detect the transmission error, must by upper entity or with correction ability to solve the problem of MODEM errors.SLIP is a kind of serial line I P data submitted to encapsulate the simple forms, in Romkey RFC 1055 [1988] are detailed description. SLIP suitable for family each computer almost all some R S - 2 3 2 serial port and high-speed modems access the Internet.Following rules describe the SLIP agreement defined frame format:1) IP data with a snarl called END (0 x c 0) special characters over. Meanwhile, in order to prevent data report before the line noise as data submitted to the content, most realize in data submitted to the start point also handed a E N D characters (if there is a line noise, then E N D characters will end this error message. So the current message to correctly transfter, before an error message to the upper, will find its content is meaningless and be thrown away.2) if I P message of some characters to END, so be about continuous transmission two bytes 0 x d b and 0 x d c to replace it.0 x d b this special characters called SLIP the ESC character, but its value and ASCII characters of the E S C (0 x 1 b) different.3) if I P message in a character to SLIP the ESC characters, so be about continuous transmission two bytes 0 x d b and 0 x d d to replace it.SLIP is a simple frame encapsulation methods, and some worth mentioning defects:1) each end must know each other's I P address. No way to put this end I P address notice to the other end.2) data frames without type fields (similar to the type field). Ethernet If a serial line used to SLIP, it cannot simultaneously use other agreement.3) no SLIP in data frames plus inspection and (similar to Ethernet in CRC field). If the message is SLIP transmission line noise effects and errors occur, only through the upper agreements to find (another method is, the new modems can detect and correct errors a message). So, the upper level protocol offer some form of CRC becomes very important.