From ea7f48ba12c2d2d5c608a58bd640c833e4a6583f Mon Sep 17 00:00:00 2001 From: shango-wk Date: Sat, 25 Apr 2026 01:09:26 +0200 Subject: [PATCH] ajout IPV4 part 1 --- 00. Jeremy's IT LAB CCNA course.md | 4 +- 07. IPv4 Addressing (Part 1).md | 75 ++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 1 deletion(-) create mode 100644 07. IPv4 Addressing (Part 1).md diff --git a/00. Jeremy's IT LAB CCNA course.md b/00. Jeremy's IT LAB CCNA course.md index c496c0a..6658ac3 100644 --- a/00. Jeremy's IT LAB CCNA course.md +++ b/00. Jeremy's IT LAB CCNA course.md @@ -14,4 +14,6 @@ tags: [[Interfaces and Cables - CCNA]] [[How the TCPIP Model Actually Works]] [[Intro to the CLI]] -[[Ethernet LAN Switching]] +[[Ethernet LAN Switching (part 1)]] +[[Ethernet LAN Switching (part 2)]] +[[IPv4 Addressing (Part 1)]] diff --git a/07. IPv4 Addressing (Part 1).md b/07. IPv4 Addressing (Part 1).md new file mode 100644 index 0000000..a3dcf77 --- /dev/null +++ b/07. IPv4 Addressing (Part 1).md @@ -0,0 +1,75 @@ +--- +id: 07. IPv4 Addressing (Part 1) +aliases: [] +tags: [] +--- + +# IPv4 Addressing (Part 1) + +## [[OSI Model]] + +- Provides connectivity between end hosts on different networks +(ie. outside of the [[LAN]]) +- Provides logical addressing [[IP addresses]] +- Provides path selection between source and destination +- [[Routers]] operate at Layer 3 + +## IPv4 Header + +IP addresses are 32 bits long + +Class A +192.168.1.254/24 +192.168.1. = network portion (part of the same network) +254 = host portion (different machine) + +Class B +154.78.111.32/16 +154.78 = network portion +111.32 = host portion + +Class C +12.128.151.23/8 +12 = network portion +128.151.23 = host portion + +## [[IPV4]] address classes + + +| Class |First octet | numeric range| Prefix Length | +| ----- | ---------- | --------------| /8 | +| A |0xxxxxxxx | 0-127 | /16 | +| B |10xxxxxxx | 128-191 | /24 | +| C |110xxxxxx | 192-223 | | +| D |1110xxxxx | 224-239 | | +| E |1111xxxxx | 240-255 | | + + +class D are reserverd for Multicast addresses +class E are reserved for expermital +end of the class A is 126 +127 are reserved for loopback addresses + +## Loopback addresses + +- Address range 127.0.0.0 - 127.255.255.255 +- Used to test the 'network stack' (think OSI, TCP/IP model) on local device + +## Netmask + +Class A: /8 255.0.0.0 +Class B: /16 255.255.0.0 +Class C: /24 255.255.255.0 + +Host portion of the address is all 0's = Network Address +the netowrk address cannot be assigned to a host + +Host portion of the address is all 1's = Broadcast address Address +The Broadcast address cannot be assigned to a host + +## Review + +- Network portion / host portion of IPv4 address +- IPv4 classes +- Prefix lengths / netmasks +- Network address / broadcast addresses