Hi, I am using Motorola H.24 modem module with the external TCP/IP stack. It seems like the H.24 modem module never send the network side (remote side) IP address during the PPP negotiation. The following trace (from bottom to top) is capture that turn on the IPCP negotiation: 119 : ipcp: down 119 : Could not determine remote IP address 119 : ipcp: up 119 : fsmOut:8-FF03802102050004 119 : ipcp: returning Configure-ACK 119 : input: 01050004 119 : fsmOut: FF0380210304000A030600000000 119 : ipcp: returning Configure-NAK 119 : input: 01040004 119 : fsmOut: FF0380210303000A030600000000 119 : ipcp: returning Configure-NAK 119 : input: 01030004 119 : input: 0203001603060AD3830D81060A0002FE83060A020224 119 : fsmOut: FF0380210302000A030600000000 119 : ipcp: returning Configure-NAK 119 : input: 01020004 119 : fsmOut: FF0380210103001603060AD3830D81060A0002FE83060A020224 119 : local IP address 10.211.131.13 119 : input: 0302001603060AD3830D81060A0002FE83060A020224 119 : fsmOut: FF0380210301000A030600000000 119 : ipcp: returning Configure-NAK 119 : input: 01010004 119 : fsmOut: FF03802101020016030600000000810600000000830600000000 119 : input: 0401000A0206002D0F01 119 : fsmOut:FF0380210300000A030600000000 119 : ipcp: returning Configure-NAK 119 : input: 01000004 116 : fsmOut: FF0380210101001C0306000000000206002D0F01810600000000830600000000 116 : Connect: ppp0 <--> /dev/ser0 116 : synxModuleConnectPSD: Success.. 113 : synxModuleConnectPSD.. 109 : synxModuleInit: success.. 106 : synxModuleInit: ATE1.. 101 : synxModuleInit: ATZ.. 101 : synxModuleInit.. 98 : synxModuleOn: Success.. 97 : synxModuleOn.. 96 : thttpd/2.20c 21nov01 starting on port 80 96 : Using interface ppp0