-all Don't request/allow any options -ac Disable Address/Control compress -am Disable asyncmap negotiation -as set the desired async map -d Increase debugging level debug Increase debugging level dialup Do special stuff for dialup -ip Disable IP address negotiation -mn Disable magic number negotiation -mru Disable mru negotiation mru Set MRU value for negotiation -p Set passive mode -s Set silent mode -pc Disable protocol field compress passive Set passive mode silent Set silent mode +pap Require UPAP authentication -pap Don't allow UPAP authentication +chap Require CHAP authentication -chap Don't allow CHAP authentication vjmode set VJ compression mode -vj disable VJ compression -vjccomp disable VJ connection-ID compression vj-max-slots Set maximum VJ header slots sync operate in synchronous HDLC mode domain Add given domain name to hostname netmask set netmask unit Set Unit request slip Do SLIP framing dynamic Allow Dynamic addresses name Set local name for authentication user Set username for PAP auth with peer usehostname Must use hostname for auth. remotename Set remote name for authentication auth Require authentication from peer login Use system password database for UPAP pap-restart Set timeout for UPAP pap-max-authreq Set max #xmits for auth-reqs chap-restart Set timeout for CHAP chap-max-challenge Set max #xmits for challenge chap-interval Set interval for rechallengeIf you need further information on these options, the best source of information is probably the source code itself.
In order to determine what is going on with all this negotiation, you can set LOG_LEVEL=3 in the conf file, and enable syslog output in your /etc/syslog.conf file. This syslog entry seems to work well:
local2.emerg;local2.alert;local2.emerg;local2.crit;local2.err /var/adm/dp/ppp.log local2.warning;local2.notice;local2.info;local2.debug /var/adm/dp/ppp.logIn examining the syslog output of PPP, you can often tell where the PPP negotiation is failing and just set the options so that the negotiation works first time.
In versions of dp prior to dp-3.1.4, VJ compression was not automatically negotiated properly. For this reason, dp-3.1.4 or newer is highly recommended
There have been at least 3 different Van Jacobsen Header compression negotiations in use since PPP became widely used. The original "rfc1172" scheme was used by the very earliest versions of dp. At some point, the default was changed to "pre1332" which used the new option value, but used the old options. Both of these older negotiations assume CID compression and 16 slots. "rfc1332" compression allows negotiation of the number of slots and the ability to enable or disable CID compression. dp-3.1.4 and newer seems to handle this correctly and it now defaults to using "rfc1332". Some effort was made to make dp-3.1.4 backward compatible with older VJ negotiations. By using the PPP_ARGS setting in the conf file, you can enable the older negotiations as follows:
Negotiation Negotiation
Option Value Option Length
PPP_ARGS=rfc1172 0x2d (45) 4
PPP_ARGS=pre1332 0x37 (55) 4
PPP_ARGS=rfc1332 0x37 (55) 6 (default)
If need be, in dp-3.1.4 or later, you can disable CID compression
with the option "PPP_ARGS=-vjccomp". In addition, you can set the number of
slots by using "PPP_ARGS=vj-max-slots,N", where N is between 3 and 254.
These options have been tested with a Xyplex terminal server.