|  | 9.1 | OSI Model
| 9.1.7 | Data link layer

The Data Link layer provides reliable transit of data across a physical link. In so doing, the data link layer is concerned with physical (as opposed to network, or logical) addressing, network topology, line discipline (how end systems use the network link), error notification, ordered delivery of frames, and flow control. The Data Link layer is responsible for delivery of the frame from one node to the next, i.e., from host to host, host to router, router to router, or router to host. The data link addresses will usually change, representing the current data link address and the next hop data link address. In terms of Ethernet, this would be the Source MAC address and the Destination MAC address. Data Link Layer protocols include: Ethernet IEEE 802.3 Token Ring IEEE 802.5 HDLC (High-level Data Link Control) PPP (Point-to-Point Protocol)
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