[network] HDLC, PPP, Frame Relay

♦ HDLC
- High-level Data Link Control
- 상대장비가 하나일 때 사용하는 WAN용 프로토콜
- 목적 : 데이터 전달, 에러 점검, 패킷 종류 확인
- 표준 프레임과 시스코 전용 프레임 차이점 : 시스코 전용 프레임은 control 과 information 사이에 type 구간이 있음

♦ PPP
- Point-to-Point protocol
- 상대 장비가 하나일 때 사용하는 WAN용 프로토콜
- 다른 L2 프로토콜과 달리 인증 기능이 있음
- 사용 구간 : 라우터간 연결할 때 시리얼 인터페이스로 연결시

♦ 프레임 릴레이
- DLCI(data link connection identifier)를 이용하여 목적지별 채널 구분
- 다양한 토폴로지 구성 가능
- 대부분 라우터 사이에 프레임 릴레이 스위치 있음
- 프레임 구성 : Flag - address - data - fcs - Flag

♦ 서브 인터페이스
- 네트워크에 비해 인터페이스 부족할 때 사용
- point-to-point 와 multi-point가 있음
- 연결되는 상대 라우터가 여러개면 multi-point 사용

♦ DLCI 매핑
- 인접 IP주소와 연결되는 DLCI번호를 지정하는 것
- point-to-point 일 때 설정 : frame-relay interface-dlci
- multi-point 일 때 설정: frame-relay map


♦ HDLC
- High-level Data Link Control
- Protocol for WAN used when there is one partner device
- Purpose: Data transfer, error check, packet type check
- Difference between standard frame and Cisco dedicated frame: Cisco dedicated frame has type interval between control and information

♦ PPP
- Point-to-Point protocol
- Protocol for WAN used when there is one partner device
- Unlike other L2 protocols, it has authentication capability.
- Usage interval: When connecting to the router through the serial interface

♦ Frame Relay
- Distinguish channel by destination using DLCI (data link connection identifier)
- Various topologies can be configured
- Most of the time there is a frame relay switch between routers.
- Frame configuration: Flag - address - data - fcs - Flag

♦ Subinterface
- Use when interface is insufficient compared to network
- There are point-to-point and multi-point
- If there are several relative routers connected, multi-point use

♦ DLCI mapping
- to specify the DLCI number associated with the neighboring IP address
- Point-to-point when set: frame-relay interface-dlci
- Setting when multi-point: frame-relay map


♦ HDLC
--tingkat Luhur Data Link Control
- protokol pikeun Wan ngagunakeun nalika salah téh relatif Equipment
- Tujuan: Pikeun mastikeun leres mindahkeun data, kasalahan mariksa, sarta tipe packet
- pigura baku sarta béda pigura husus pikeun Cisco: Cisco yen mung tipe pigura jeung interval antara informasi kontrol

♦ PPP
- Point-to-Point protokol
- protokol pikeun Wan ngagunakeun nalika salah téh relatif Equipment
- yén fungsi auténtikasi kawas protokol sejen L2
- Paké interval, nalika disambungkeun ka panganteur serial nyambungkeun hiji router-to-router

♦ kotakna Relay
- DLCI tujuan pikeun tiap channel dipisahkeun ku maké (data sambungan link identifier)
- Sagala rupa topologies bisa ngonpigurasi
- anu pigura relay switch antara paling routers
- pigura konstruksi: Citakan: Country data - alamat - data - fcs - Citakan: Country data

♦ sub-panganteur
- panganteur pamaké téh low lamun dibandingkeun jaringan nu
- Dina hiji titik-ka-titik na multi-titik
- Mun aya sababaraha disambungkeun router éksternal pamakéan multi-titik

♦ pemetaan DLCI
- nepi ka tangtukeun jumlah DLCI nu disambungkeun ka alamat IP meungkeut
- titik-ka-titik nalika hiji set: pigura-relay panganteur-dlci
- multi-titik nalika hiji set: peta pigura-relay