Library /sys$common/syshlp/ncphelp.hlb SET, LINE, TRANSMIT PIPELINE number  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Applies only to DMR11 lines.  Specifies the maximum number of DDCMP
 messages for which outstanding acknowledgments are allowed.  Specify a
 value in the range 1 to 32.  By default, the value for outstanding
 DDCMP messages is 7.  To avoid excessive use of system memory, do not
 arbitrarily set this value higher than necessary.  Refer to the DECnet
 for OpenVMS Networking Manual for the procedure for determining an
 optimum TRANSMIT PIPELINE value.