vlan
개념
- VLAN 이란 Virtual Local Area Network 의 약자로 물리적 배치와 상관없이 논리적으로 LAN을 구성할 수 있는 기술
장점
- [ㄱ] 보안 : 네트워크의 다른 부분과 분리되어 보안의 장점
- [ㄴ] 비용절감 : 기존 대역폭과 업링크의 사용을 효울적이게 해줌
- [ㄷ] 높은 성능
- [ㄹ] 2계층 네트워크를 다수의 논리적 그룹(broadcast domain)으로 분리하며 필요없는 트래픽을 줄임 [* 브로드캐스트 스톰 방지]
[*브로드 캐스트 도메인 : LAN 상에서 어떤 단말이 브로드캐스트 패킷을 송실할 때, 이 패킷에 대해 '네트워크에서 영향 받는 영역']
VLAN 간의 통신은 라우터를 통해서만 가능
=> 같은 VLAN 이라면, 다른 스위치라도 통신 가능
트렁크 포트(Trunk Port)
=> 하나의 포트를 통해 서로 다른 여러개의 VLAN을 전송할 수 있게 하는 포트
VLAN의 종류
=> static vlan
default VLAN 설정 - VLAN 1 로 설정
Switch#show vlan //vlan 정보 확인
Switch(config)#vlan 12 // vlan 12 생성
Switch(config)#do show vlan
Switch(config)#no vlan 12 // vlan 12 삭제
추가한 VLAN에 해당 포트들을 지정
Switch(config)#INterface FAstEthernet 0/2
Switch(config-if)#SWitchport access vlan 12
트렁크 설정
switchport mode trunk
라우터 설정
Router(config-subif)#encapsulation do
Router(config-subif)#encapsulation dot1Q 13
Router(config-subif)#ip address 192.168.11.1 255.255.255.0
Router(config-subif)#no shutdown
Switch(config)#interface fastEthernet 0/1
Switch(config-if)#switchport mode trunk
공부
------------------ cmd ------------------------
1) ping -n 1 8.8.8.8
[ping -n x(x번을 의미한다.)]
1-1) ping 8.8.8.8
-> 기본적으로 4번 실행한다.
1-2) ping -l 1400 -n 1 8.8.8.8
1-3) ping -f -l 2000 -n 1 8.8.8.8
(-f는 Do Not Fragment)
2) arp -a
arp -d
3) netstat -r
4) ipconfig /all
L4: port address
->http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml
port: 16bit -> 0~ 65535
A - 0
- 1
...
-65535
[ Port == Service ]
System Port(Well Known Port)
:web은 80 예를들어 www.naver.com:80
User Port(Registered Port)
:사용자 등록 Port
Dynamic/Private
:누구든지 사용할 수 있다.
http:80
smtp:25
192.168.0.0
(2^n = 2, n=1)
NNNNNNNN-NNNNNNNN-NNNNNNNN-HHHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-NHHHHHHH
[1]: NNNNNNNN-NNNNNNNN-NNNNNNNN-0HHHHHHH
(1)Range:NNNNNNNN-NNNNNNNN-NNNNNNNN-00000000 NNNNNNNN-NNNNNNNN-NNNNNNNN-01111111
192.168.0.0 ~ 192.168.0.127
(2)192.168.0.0
(3)192.168.0.127
(4)192.168.0.1 ~ 192.168.0.126
comp1:192.168.0.1
comp2:192.168.0.2
comp3:192.168.0.3
gateway:192.168.0.126
[2] NNNNNNNN-NNNNNNNN-NNNNNNNN-1HHHHHHH
(2^n = 2, n=1)
NNNNNNNN-NNNNNNNN-NNNNNNNN-1NHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-10HHHHHH
(1)Range:NNNNNNNN-NNNNNNNN-NNNNNNNN-10000000 NNNNNNNN-NNNNNNNN-NNNNNNNN-10111111
192.168.0.128 ~ 192.168.0.191
(2)192.168.0.128
(3)192.168.0.191
(4)192.168.0.129 ~ 192.168.0.190
comp4:192.168.0.129
comp5:192.168.0.130
comp6:192.168.0.131
gateway:192.168.0.190
NNNNNNNN-NNNNNNNN-NNNNNNNN-11HHHHHH
(1)Range:NNNNNNNN-NNNNNNNN-NNNNNNNN-11000000 NNNNNNNN-NNNNNNNN-NNNNNNNN-11111111
192.168.0.192 ~ 192.168.0.255
(2)192.168.0.192
(3)192.168.0.255
(4)192.168.0.193 ~ 192.168.0.254
comp7:192.168.0.193
comp8:192.168.0.194
comp9:192.168.0.195
gateway:192.168.0.254
192.168.1.0
NNNNNNNN-NNNNNNNN-NNNNNNNN-HHHHHHHH
(1)Range: 192.168.1.0 ~ 192.168.1.255
(2)192.168.1.0
(3)192.168.1.255
(4)192.168.1.1 ~ 192.168.1.254
comp10:192.168.1.2
comp11:192.168.1.3
comp12:192.168.1.4
gateway:192.168.1.254
공부
network
C-class
[ 192.168.0.0/24 ]
NNNNNNNN - NNNNNNNN - NNNNNNNN - HHHHHHHH
2개로 분할(2^n = 2, 따라서 n은 1)
NNNNNNNN - NNNNNNNN - NNNNNNNN - NHHHHHHH
1. NNNNNNNN - NNNNNNNN - NNNNNNNN - 0HHHHHHH
[1] Range: NNNNNNNN - NNNNNNNN - NNNNNNNN - 00000000
~ NNNNNNNN - NNNNNNNN - NNNNNNNN - 01111111
192.168.0.0 ~ 192.168.0.127
[2] Network Address : 192.168.0.0
[3] Host Address : 192.168.0.1 ~ 192.168.0.126
[4] Broadcast Address: 192.168.0.127
[5] Subnet Mask : 255.255.255.128
PC-PT PC0 -> 192.168.0.1
PC-PT PC1 -> 192.168.0.2
PC-PT PC2 -> 192.168.0.3
GATEWAY: 192.168.0.126
2. NNNNNNNN - NNNNNNNN - NNNNNNNN - 1HHHHHHH
[1] Range: NNNNNNNN - NNNNNNNN - NNNNNNNN - 10000000
~ NNNNNNNN - NNNNNNNN - NNNNNNNN - 11111111
192.168.0.128 ~ 192.168.0.255
[2] Network Address : 192.168.0.128
[3] Host Address : 192.168.0.129 ~ 192.168.0.254
[4] Broadcast Address: 192.168.0.255
[5] Subnet Mask : 255.255.255.128
PC-PT PC3 -> 192.168.0.129
PC-PT PC4 -> 192.168.0.130
PC-PT PC5 -> 192.168.0.131
GATEWAY: 192.168.0.254
[ping xxx.xxx.xxx.xxx]
공부4
IPv4 -->https://en.wikipedia.org/wiki/IPv4#Private_networks
<-------- C: class 192.168.0.0/24
C - class 192.168.0.0/24
(2^n = 2, 따라서 n = 1)
NNNNNNNN-NNNNNNNN-NNNNNNNN-HHHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-NHHHHHHH
--> NNNNNNNN-NNNNNNNN-NNNNNNNN-0HHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-00000000 ~ NNNNNNNN-NNNNNNNN-NNNNNNNN-01111111
192.168.0.0/25 ~ 192.168.0.127/25
[1]192.168.0.0/25
[2]192.168.0.1/25 ~ 192.168.0.126/25
[3]192.168.0.127/25
[4]GATEWAY:192.168.0.126/25
PC-PT (PC1:192.168.0.1/25)
PC-PT (PC2:192.168.0.2/25)
PC-PT (PC3:192.168.0.3/25)
--> NNNNNNNN-NNNNNNNN-NNNNNNNN-1HHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-10000000 ~ NNNNNNNN-NNNNNNNN-NNNNNNNN-11111111
192.168.0.128/25 ~ 192.168.0.255/25
[1]192.168.0.128/25
[2]192.168.0.129/25 ~ 192.168.0.255/25
[3]192.168.0.255/25
[4]GATEWAY:192.168.0.254/25
PC-PT (PC1:192.168.0.129/25)
PC-PT (PC2:192.168.0.130/25)
PC-PT (PC3:192.168.0.131/25)
studing
2016년 02월 18일
보안 3일차-------------------------------------------------------------------------------------
A
C class----------------------------------------
NNNNNNNN-NNNNNNNN-NNNNNNNN-HHHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-NHHHHHHH (2^n = 2 따라서 n = 1)
NNNNNNNN-NNNNNNNN-NNNNNNNN-0HHHHHHH
->NNNNNNNN-NNNNNNNN-NNNNNNNN-00000000 ~ NNNNNNNN-NNNNNNNN-NNNNNNNN-01111111
->NNNNNNNN-NNNNNNNN-NNNNNNNN-10000000 ~ NNNNNNNN-NNNNNNNN-NNNNNNNN-11111111
200.100.50.0
200.100.50.128/25
NNNNNNNN-NNNNNNNN-NNNNNNNN-NHHHHHHH (2^n = 2 따라서 n = 1)
NNNNNNNN-NNNNNNNN-NNNNNNNN-1NHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-10HHHHHH -> NNNNNNNN-NNNNNNNN-NNNNNNNN-10000000
~NNNNNNNN-NNNNNNNN-NNNNNNNN-10111111
200.100.50.128/26 ~ 200.100.50.191/26
Network Address : 200.100.50.128/26
Host Address : 200.100.50.129/26 ~ 200.100.50.190/26
Broadcast Address: 200.100.50.191/26
Subnet Mask : 255.255.255.192
NNNNNNNN-NNNNNNNN-NNNNNNNN-11HHHHHH -> NNNNNNNN-NNNNNNNN-NNNNNNNN-11000000
~NNNNNNNN-NNNNNNNN-NNNNNNNN-11111111
200.100.50.192/26 ~ 200.100.50.255/26
Network Address : 200.100.50.192/26
Host Address : 200.100.50.193/26 ~ 200.100.50.254/26
Broadcast Address: 200.100.50.255/26
Subnet Mask : 255.255.255.192
호스트가 32대가 들어갈 수 있는 최소한의 네트워크는? 2^n -2(Network, Broad) >=32
C - class
192.168.20.0/24 -> 256-2 = 254
NNNNNNNN-NNNNNNNN-NNNNNNNN-NHHHHHHH (2^n = 2 따라서 n = 1)
NNNNNNNN-NNNNNNNN-NNNNNNNN-0HHHHHHH
->NNNNNNNN-NNNNNNNN-NNNNNNNN-00000000 ~ NNNNNNNN-NNNNNNNN-NNNNNNNN-01111111
192.168.20.0/25 ~ 192.168.20.127/25 128-2 = 126
->
NNNNNNNN-NNNNNNNN-NNNNNNNN-1HHHHHHH
->NNNNNNNN-NNNNNNNN-NNNNNNNN-10000000 ~ NNNNNNNN-NNNNNNNN-NNNNNNNN-11111111
192.168.20.128/25 ~ 192.168.20.255/25
NNNNNNNN-NNNNNNNN-NNNNNNNN-1NHHHHHH
NNNNNNNN-NNNNNNNN-NNNNNNNN-10HHHHHH
->192.168.20.128/26 ~ 192.168.20.191/26 64-2 = 62
NNNNNNNN-NNNNNNNN-NNNNNNNN-11HHHHHH
->192.168.20.192/26 ~ 192.168.20.255/26
P2P Network ->NNNNNNNN-NNNNNNNN-NNNNNNNN-NNNNNNNHH 01 --- 10
192.168.20.0/30
255.255.255.255 상징적 의미를 가진다.
192.168.0.101/32
------------------(AND)
192.168.0.101/32
->IP임을 알려준다
집에가서 할일
해야 될 일
-> 네트워크 책 다시 찾아보기
-> 오늘 배운거 정리 하기
공부3
Terminology: 전문용어
Network <-Share(A computer -> B computer): American
ARPA(Advanced Research -) ->ARPA net
DoD(Depart of Defence) ->DARPA(Defence --) -> DARPAnet
IPv4 ---> IPv6
Protocol(통신 규약): language
(Ethernet/ ARP/ ICMP/ IP/ TCP/ UDP): Network의 핵심이다.
Circuit Switching vs Packet Switching
(telephone) (internet)
Packet switching is a digital networking communications method that
groups all transmitted data into suitably sized blocks, called packets,
which are transmitted via a medium that may be shared by multiple simultaneous communication sessions.
Packet switching increases network efficiency,
robustness and enables technological convergence of many applications operating on the same network.
---------------------------------------------------------------------------------
https://en.wikipedia.org/wiki/OSI_model
https://en.wikipedia.org/wiki/MAC_address
http://standards-oui.ieee.org/oui.txt
http://www.macvendorlookup.com/
https://en.wikipedia.org/wiki/Classful_network#Introduction_of_address_classes
---------------------------------------------------------------------------------
1.x.x.x
A Class Subnet Mask(SM) :255.0.0.0
00000001.xxxxxxxx.xxxxxxxx.xxxxxxxx
11111111.00000000.00000000.00000000 == 255.0.0.0
------------------------------------(AND)
00000001.00000000.00000000.00000000 ==> 1.0.0.0 (Network Address)
1.1.1.1의 네트워크 address =>1.0.0.0
1.2.3.4/8 --->1.0.0.0
192.168.0.1/24
C Class Subnet Mask: 255.255.255.0
공부
192.168.0.0/24 C class
192.168.0.0~ 192.168.0.255 Range
192.168.0.0 Network Address
192.168.0.1~192.168.0.254 Host Address(컴퓨터에 부여)
192.168.0.255 Network Broadcast
==================================================================
<LAN 1>
192.168.0.0 ~192.168.0.127 IP Range
192.168.0.0 Network Address
192.168.0.1 ~192.168.0.126 Host Address
192.168.0.127 Network Broadcast
------------------------------------------------------------------
<LAN 2>
192.168.0.128 ~192.168.0.255
192.168.0.128 Network Address
192.168.0.129 ~192.168.0.254 Host Address
192.168.0.255 Network Broadcast
example)
NNNNNNNN.NNNNNNNN.NNNNNNNN.HHHHHHHH
NNNNNNNN.NNNNNNNN.NNNNNNNN.NHHHHHHH (N = 0 or 1)
NNNNNNNN.NNNNNNNN.NNNNNNNN.0HHHHHHH/ 25
---> NNNNNNNN.NNNNNNNN.NNNNNNNN.0000000
NNNNNNNN.NNNNNNNN.NNNNNNNN.0111111
11111111.11111111.11111111.1000000 (AND)
-----------------------------------------------------
NNNNNNNN.NNNNNNNN.NNNNNNNN.1HHHHHHH/ 25
---> NNNNNNNN.NNNNNNNN.NNNNNNNN.1000000
NNNNNNNN.NNNNNNNN.NNNNNNNN.1111111
11111111.11111111.11111111.1000000 (AND)
-----------------------------------------------------
C - class
200.100.50.0/24 - network를 4개로 나우시오
NNNNNNNN.NNNNNNNN.NNNNNNNN.HHHHHHHH -> NNNNNNNN.NNNNNNNN.NNNNNNNN.NNHHHHHH (2^n = 4, 따라서 n은 2개(N))
NNNNNNNN.NNNNNNNN.NNNNNNNN.00HHHHHH -> NNNNNNNN.NNNNNNNN.NNNNNNNN.00[000000] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.00[111111]
[1]Network Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.00[000000]
[2]Host Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.00[000001] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.00[1111110]
[3]Broadcast Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.00[111111]
[4]Subnet Mask Address: 11111111.11111111.11111111.11000000 ->255.255.255.192
NNNNNNNN.NNNNNNNN.NNNNNNNN.01HHHHHH -> NNNNNNNN.NNNNNNNN.NNNNNNNN.01[000000] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.01[111111]
[1]Network Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.01[000000]
[2]Host Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.01[000001] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.01[111110]
[3]Broadcast Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.01[111111]
[4]Subnet Mask Address: 11111111.11111111.11111111.11000000 ->255.255.255.192
NNNNNNNN.NNNNNNNN.NNNNNNNN.10HHHHHH -> NNNNNNNN.NNNNNNNN.NNNNNNNN.10[000000] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.10[111111]
[1]Network Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.10[000000]
[2]Host Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.10[000001] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.10[111110]
[3]Broadcast Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.10[111111]
[4]Subnet Mask Address: 11111111.11111111.11111111.11000000 ->255.255.255.192
NNNNNNNN.NNNNNNNN.NNNNNNNN.11HHHHHH -> NNNNNNNN.NNNNNNNN.NNNNNNNN.11[000000] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.11[111111]
[1]Network Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.11[000000]
[2]Host Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.11[000001] ~ NNNNNNNN.NNNNNNNN.NNNNNNNN.11[111110]
[3]Broadcast Address : NNNNNNNN.NNNNNNNN.NNNNNNNN.11[111111]
[4]Subnet Mask Address: 11111111.11111111.11111111.11000000 ->255.255.255.192
B - class
169.20.0.0/16 - network를 2개로 나누시오
NNNNNNNN.NNNNNNNN.HHHHHHHH.HHHHHHHH -> NNNNNNNN.NNNNNNNN.HHHHHHHH.HHHHHHHH (2^n = 2, 따라서 n은 1개(N))
NNNNNNNN.NNNNNNNN.0HHHHHHH.HHHHHHHH -> NNNNNNNN.NNNNNNNN.0[0000000.00000000] ~ NNNNNNNN.NNNNNNNN.0[1111111.11111111]
169.20.0.0 ~ 169.20.127.255
[1]Network Address : NNNNNNNN.NNNNNNNN.0[0000000.00000000]: 169.20.0.0
[2]Host Addrss : NNNNNNNN.NNNNNNNN.0[0000000.00000001] ~ NNNNNNNN.NNNNNNNN.0[1111111.11111110] 169.20.0.1 ~ 169.20.127.254
[3]Broadcast Address : NNNNNNNN.NNNNNNNN.0[1111111.11111111]: 169.20.127.255
[4]Subnet Mask Address: 11111111.11111111.10000000.00000000 ->255.255.128.0
NNNNNNNN.NNNNNNNN.1HHHHHHH.HHHHHHHH -> NNNNNNNN.NNNNNNNN.1[0000000.00000000] ~ NNNNNNNN.NNNNNNNN.1[1111111.11111111]
169.20.128.0 ~ 169.20.128.255
[1]Network Address : NNNNNNNN.NNNNNNNN.1[0000000.00000000] 169.20.128.0
[2]Host Address : NNNNNNNN.NNNNNNNN.1[0000000.00000001] ~ NNNNNNNN.NNNNNNNN.1[1111111.11111110] 168.20.128.1 ~168.20.255.254
[3]Broadcast Address : NNNNNNNN.NNNNNNNN.1[1111111.11111111] 168.20.255.255
[4]Subnet Mask Address: 11111111.11111111.10000000.00000000 ->255.255.128.0
네트워크 범위
네트워크 주소
호스트 주소
네트워크 Broadcast address
서브넷 마스크 주소
