IPv4.docx

**Module 11: IPv4 Addressing** **IPv4 Address Structure Network and Host Portions:** *(Insert picture illustrating the division between the network and host portions)* **The Subnet Mask:** *(Insert picture showing the process of ANDing with subnet mask)* **The Prefix Length:** **Subnet Mask**...

**Module 11: IPv4 Addressing** **IPv4 Address Structure Network and Host Portions:** *(Insert picture illustrating the division between the network and host portions)* **The Subnet Mask:** *(Insert picture showing the process of ANDing with subnet mask)* **The Prefix Length:** **Subnet Mask** **32-bit Address** ----------------- ------------------------------------- ----- 11111111.00000000.00000000.00000000 /8 11111111.11111111.00000000.00000000 /16 11111111.11111111.11111111.00000000 /24 11111111.11111111.11111111.10000000 /25 11111111.11111111.11111111.11000000 /26 11111111.11111111.11111111.11100000 /27 11111111.11111111.11111111.11110000 /28 11111111.11111111.11111111.11111000 /29 11111111.11111111.11111111.11111100 /30 **Determining the Network: Logical AND:** The logical AND operation is fundamental in calculating the network address from a given IP address and its subnet mask. This operation compares each bit of the IP address and subnet mask, resulting in the network address. *(Insert picture illustrating logical AND operation)* **Network, Host, and Broadcast Addresses:** +-----------------+-----------------+-----------------+-----------------+ | **Address | **Example | **Binary | **Notes** | | Type** | (IPv4** | Representation* | | | | | * | | | | **/24)** | | | +=================+=================+=================+=================+ | | 192.168.10.0 | 11000000.101000 | All host bits | | | | 00.00001010.000 | are | | | | 00000 | | | | | | 0 | +-----------------+-----------------+-----------------+-----------------+ | | 192.168.10.1 | 11000000.101000 | First usable | | | | 00.00001010.000 | address | | | | 00001 | | +-----------------+-----------------+-----------------+-----------------+ | | 192.168.10.254 | 11000000.101000 | Last usable | | | | 00.00001010.111 | address | | | | 11110 | | +-----------------+-----------------+-----------------+-----------------+ | | 192.168.10.255 | 11000000.101000 | All host bits | | | | 00.00001010.111 | are | | | | 11111 | | | | | | 1 | +-----------------+-----------------+-----------------+-----------------+ **IPv4 Unicast, Broadcast, and Multicast Unicast:** **Example:** A PC at 172.16.4.1 sends a unicast packet to a printer at 172.16.4.253. **Broadcast:** **Multicast:** Multicast involves sending data to a group of devices that have expressed interest in receiving it. This method is efficient for distributing data to multiple recipients without burdening the entire network. **Example:** A PC at 172.16.4.1 sends a multicast packet to a multicast group address like 224.10.10.5. **Types of IPv4 Addresses Public and Private IPv4 Addresses:** **Range** **Note** -- ------------------------------- ---------------------- 10.0.0.0 - 10.255.255.255 Large private block 172.16.0.0 - 172.31.255.255 Medium private block 192.168.0.0 - 192.168.255.255 Small private block **Routing to the Internet:** **NAT (Network Address Translation):** Translates private IP addresses to public IP addresses, enabling internal devices to access the internet. NAT is usually configured on the edge router of a network. **Special Use IPv4 Addresses:** **Legacy Classful Addressing:** Originally, IPv4 addresses were divided into classes (A, B, C, D, E) based on the leading bits of the address. This method was replaced by classless addressing to avoid wastage of IP addresses. **Range** -- ----------------------------- --------------- 0.0.0.0 - 127.255.255.255 255.0.0.0 128.0.0.0 - 191.255.255.255 255.255.0.0 192.0.0.0 - 223.255.255.255 255.255.255.0 224.0.0.0 - 239.255.255.255 \- 240.0.0.0 - 255.255.255.255 \- **Assignment of IP Addresses:** The **Internet Assigned Numbers Authority (IANA)** manages the global pool of IP addresses and allocates them to the **Regional Internet Registries (RIRs)**, which then allocate them to ISPs and organizations. **Network Segmentation Broadcast Domains and Segmentation:** **Broadcast Domains:** A logical division of a computer network, where all nodes can reach each other by broadcast at the data link layer. Routers are used to separate broadcast domains, preventing broadcast traffic from overwhelming the network. **Problems with Large Broadcast Domains:** Large broadcast domains can lead to excessive broadcast traffic, reducing network efficiency. Subnetting can mitigate this by dividing a network into smaller, more manageable segments. **Reasons for Segmenting Networks:** **Subnetting:** Improves network performance, enhances security, and reduces the number of devices affected by network issues. Subnets can be organized by location, function, or device type. **Subnetting an IPv4 Network Subnet on an Octet Boundary:** Subnetting can be easily done on the boundaries of octets (/8, /16, /24), allowing for a straightforward division of network and host portions. ---- ----------- -- -- /8 255.0.0.0 ---- ----------- -- -- \| /16 \| 255.255.0.0 \| 11111111.11111111.00000000.00000000 \| 65,534 \| \| /24 \| 255.255.255.0 \| 11111111.11111111.11111111.00000000 \| 254 \| **Subnet within an Octet Boundary:** Further subnetting within an octet boundary can create smaller networks, allowing for efficient IP address management and network segmentation. +-----------------+-----------------+-----------------+-----------------+ | **Prefix** | **Subnet Mask** | **Subnet Mask | **\# of** | | | | (Binary)** | | | **Length** | | | **Hosts** | +=================+=================+=================+=================+ | | 255.255.255.128 | 11111111.111111 | 126 | | | | 11.11111111.100 | | | | | 00000 | | +-----------------+-----------------+-----------------+-----------------+ | | 255.255.255.192 | 11111111.111111 | 62 | | | | 11.11111111.110 | | | | | 00000 | | +-----------------+-----------------+-----------------+-----------------+ | | 255.255.255.224 | 11111111.111111 | 30 | | | | 11.11111111.111 | | | | | 00000 | | +-----------------+-----------------+-----------------+-----------------+ | | 255.255.255.240 | 11111111.111111 | 14 | | | | 11.11111111.111 | | | | | 10000 | | +-----------------+-----------------+-----------------+-----------------+ | | 255.255.255.248 | 11111111.111111 | 6 | | | | 11.11111111.111 | | | | | 11000 | | +-----------------+-----------------+-----------------+-----------------+ | | 255.255.255.252 | 11111111.111111 | 2 | | | | 11.11111111.111 | | | | | 11100 | | +-----------------+-----------------+-----------------+-----------------+ **Subnet a Slash 16 and a Slash 8 Prefix:** Large organizations may need to subnet a /16 or /8 network to provide enough subnets for different departments, geographical locations, or functions. **Subnet to Meet Requirements:** To efficiently manage IP addresses, organizations might use private IP addresses for internal networks and public IP addresses for externally accessible services. Subnetting allows organizations to optimize IP address usage and minimize wastage.