PPP Negotation Trace for one of my internet connections:
 
#1. We Send LCP Request
FF 03 C0 21 Header FF/03=ADR, C0/21=LCP
01 00 00 06 01=LCP Req / 00=id / 00=size hi / 06=size low(6)
07 02 07=Protocol compresison.  Informs other end we allow protocol field in non LCP packets to be compressed to one byte from two.
64 7B PPP Checksum;
#2. We receive an LCP Request
FF 03 C0 21 Header
01 3C 00 1C 01=LCP Req / 3C=id / 00=size hi / 1C=size low (28)
01 04 05 DC 01=MRU / 04=size / 05DC=Min Receive Unit size (1500 which is default)
02 06 00 0A 00 00 02=ACCM option / 06=size /  000A0000=All chars but 17 and 19 (control q and control s) can be sent without escaping
05 06 01 00 00 00 05=Magic Number option / 06=size / 01000000=magic number
07 02 07=Protocol compresison / 02=size  Other end allows protocol field in non LCP packets to be compressed to one byte from two.
08 02 08=Address and Control compression / 02=size (Informs us the other end allows the FF 03 to be eliminated in a packet)
03 04 C0 23 03=Auth Protocol / 04=size / C023=PAP  (Other side is requesting Password Authentication Protocol)
DE F4 PPP Checksum
#3. We send an LCP ACK (for #2)
FF 03 C0 21 Header
02 3C 00 1C 02=LCP Ack
01 04 05 DC Echoing back his options....
02 06 00 0A 00 00 ...
05 06 01 00 00 00 ...
07 02 ...
08 02 ...
03 04 C0 23 ...
ED AE PPP Checksum
#4. We receive an LCP Ack (for #1)
FF 03 C0 21 Header
02 00 00 06 02=LCP Ack
07 02 Echoing back our options...
19 77 PPP Checksum
#5. We Send a PAP (password authentication protocol) packet
FF 03 C0 23 Header FF/03=Adr C0/23 = LCP PAP 
01 01 00 23 01=Req / 01=id / 00=size high / 23=size low(35)
10 6B 73 69 64 65 72 73 40
77 63 6F 6D 2E 6E 65 74
10 =1 len (16) + remainder is username
0D xx xx xx xx xx xx xx xx xx
xx xx xx xx
0D = len (13) + remainder is password
B7 11 PPP Checksum
#6. We receive and ACK to our PAP (from #5)
FF 03 C0 23 Header FF/03=Adr C0/23=LCP PAP
02 01 00 05 02=Ack / 01=id / 00=size high / 05=size low
00 Message from host (If I remember correctly)
8B 3B PPP Checksum
#7. We send an IPCP request for an IP of 0.0.0.0
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
01 01 00 0A 01=Req / 01=id / 00=size high / 0A=size low(10)
03 06 00 00 00 00 Request IP of 0.0.0.0
13 28 PPP Checksum
#8. We recieve an IPCP request
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
01 3D 00 10 01=Req / 01=id / 00=size high / 10=size low(16)
02 06 00 2D 0F 01 02=IP protocol compression / 06=size / 002D=Van Jacobson Compressed TCP/IP headers / 0F=Max-Slot-Id / 01=Comp-Slot-ID
03 06 CE AF 60 FE Host IP is CE.AF.60.FE
F4 A4 PPP Checksum
#9. We reject an IPCP option (from #8)
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
04 3D 00 0A 04=Rej / 3D=id / 00=size high / 0A=size low(10)
02 06 00 2D 0F 01 Reject IP protocol compression (we got enough to worry about already!)
04 96 PPP Checksum
#10. Our IP of 0.0.0.0 was rejected (from #7) but we get an IP suggested
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
03 01 00 0A 03=Rej / 01=id / 00=size high / 0A=size low(10)
03 06 CE AF 60 8E IP of CE.AF.60.8E is suggested
F5 A8 PPP Checksum
#11. Send new request requesting the suggested IP
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
01 01 00 0A 01=Req / 01=id / 00=size high / 0A=size low(10)
03 06 CE AF 60 8E request IP of CE.AF.60.8E
BB F0 PPP Checksum
#12. Receive a new IPCP request with the option we rejected (in #9) removed
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
01 3E 00 0A 01=Req / 01=id / 00=size high / 0A=size low(10)
03 06 CE AF 60 FE Host ip again is CE.AF.60.FE
B9 1D PPP Checksum
#13 We ack his new request (from #12)
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
02 3E 00 0A 02=Ack / 3E=id / 00=size high / 0A=size low(10)
03 06 CE AF 60 FE Host ip
D0 69 PPP Checksum
#14 We receive an ACK for our request
FF 03 80 21 Header FF/03=Adr 80/21=IPCP
02 01 00 0A 02=Ack / 01=id / 00=size high / 0A=size low(10)
03 06 CE AF 60 8E Our IP of CE.AF.60.8E confirmed
D2 84 PPPChecksum
We are PPP connected!!!

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