No, the source link-layer address does not define the network; it identifies the specific device within a local network. Link-layer addresses, such as MAC addresses, are used for communication within the same local area network (LAN) and are not routable across different networks. The network itself is typically defined by its IP address range or subnet, which facilitates routing between different networks.
Latency is the time a frame or a packet takes to travel from the source to the destination.
The Provider Edge Bridges
IP source and destination address
The IP Address identifies a PC on a network. Source: I am an IT student in College :)
The data link layer header contains the source's physical address. It refers the address that is found in the Network Interface Card.
An "ip address" is a complete source or destination address that has a network id portion and a client or host portion. The network id is just a piece of the IP address. So, a public ip is an IP address that can be routed, whereas the network id is just a part of the public ip. They aren't different; the network id is part of the ip address.
The source and destination IP address can be identified.
The Layer 3(Network Layer) is associated with IP addressing.Because,It converts the frames into packets and address them to send across the other network through intermediary devices.While transferring across the other network's have to know about the destination IP address and also source IP address's deals with IP address.
Packet
network portion of ip address
As a packet traverses different networks, the source IP address will always stay the same as the original sending devices IP address unless NAT (Network Address Translation) is involved somewhere along the line.
MAC address is a unique number which is necessary for communication between computers in network. It identifies a source and destination device within a Ethernet network.