xDSL Glossary PPPoE PPP over Ethernet RFC 2516 PPPoA PPP over ATM RFC 2364 (PPP over AAL5) L2TP Layer 2 Tunneling Protocol RFC 2661 LAC L2TP Access Concentrator LNS L2TP Network Server PPPoE PADT PPPoE Active Discovery Terminate PADI PPPoE Active Discovery Initiation PADO PPPoE Active Discovery Offer PADS PPPoE Active Discovery Session-confirmation PADR PPPoE Active Discovery Request About ADSL time transmissions These values are extract from Thomson SpeedTouch's manual (release 5.3.0) Line Speed MTU 64 128 256 512 1024 1500 56 kb/s 9ms 18ms 36ms 72ms 144ms 214ms 64 kb/s 8ms 16ms 32ms 64ms 128ms 187ms 128 kb/s 4ms 8ms 16ms 32ms 64ms 93ms 256 kb/s 2ms 4ms 8ms 16ms 32ms 48ms 512 kb/s 1ms 2ms 4ms 8ms 16ms 23ms 1 Mb/s 0,640ms 1,2ms 2,6ms 5ms 10ms 15ms