Cell Relay Archive[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index][Thread Index][Author Index][Subject Index] Re: Frame retransmission when using AAL 5 ???
Ilias Andrikopoulos (eep3ia@ee.surrey.ac.uk) wrote: : Hi everybody. : Could anyone give me an answer to the following question? : Supposing we need to develop a native ATM application which will be usi= ng : AAL type 5 for transferring e.g. data. If a cell is lost for some reaso= n : and a whole packet has to be restransmitted who is responsible to do th= is? There is no mechanism to retransmit dropped AAL5-frames in the ATM protocol stack. The AAL5 protocol only has to drop frames if cells are dropped or the CRC value is incorrert. The ATM protocol only has to drop cells with invalid header information. This means that your application is responsible to detect and retransmit lost AAL5 frames. : The AAL 5 cannot - right? - so does this mean that the application must= : include transport layer functionality to support end-to-end flow : control??? Do current API implementations support this? I only know the FORE-API implementation for SOLARIS. FORE-API connections= have the same properties as UDP socket connections. The important difference is the specification of QoS-parameters. But there is no end-to-end flow control and no frame loss detection and retransmission. : Thanks, : = : Ilias : = I hope the information will help you. Diethelm ************************************************************ Diethelm Schlegel Universit=E4t des Saarlandes FB 14 Informatik - LS Prof. Paul Phone: +49 681-302-4129 Im Stadtwald - Bau 45 Raum 319 Fax: +49 681-302-4290 66123 Saarbr=FCcken, Germany Email: dst@cs.uni-sb.de ************************************************************ |
|