| A | B |
|---|
| VLAN | a logical grouping of devices or users that can be grouped by function, department, or application, regardless of their physical segment location |
| port-mapping | capability that established a broadcast domain between a default group of devices |
| LAN vs VLAN | VLANs work at Layer 2 and Layer 3 of the OSI reference model. |
| Switch port groups | Coworkers in the same department |
| VLAN Transport Capabilities | remove the physical boundaries between users |
| Backbone | commonly acts as the collection point for large volumes of traffic. It also carries end-user VLAN information and identification between switches, routers, and directly attached servers. |
| Router role in VLAN | provide firewalls, broadcast management and route processing and distribution. |
| high-speed backbone connections | Increasing the throughput between switches and routers |
| VLAN metrics | has the intelligence to make filtering and forwarding decisions by frame |
| Frame Tagging | frame filtering and frame identification, determine where the frame is to be sent, filtered, or broadcast |
| Purpose of frame tagging | uniquely assigns a VLAN ID to each frame |
| trunking | Frame tagging is gaining recognition as the standard trunking mechanism; in comparison to frame filtering, it can provide a more scalable solution to VLAN deployment that can be implemented campus-wide. IEEE 802.1q states that frame tagging is the way to implement VLANs |
| How frame tagging works | Frame tagging places a unique identifier in the header of each frame as it is forwarded throughout the network backbone. The identifier is understood and examined by each switch prior to any broadcasts or transmissions to other switches, routers, or end-station devices. When the frame exits the network backbone, the switch removes the identifier before the frame is transmitted to the target end station |
| VLAN implementation methods | port-centric |
| Port Centric VLANS | all the nodes connected to ports in the same VLAN are assigned to the same VLAN ID |
| Port Centric Benefits | Users are assigned by port. |
| Static VLANS | ports on a switch that you statically assign to a VLAN. These ports maintain their assigned VLAN configurations until you change them |
| Static VLAN Benefits | they are secure, easy to configure, and straightforward to monitor |
| Dynamic VLANs | ports on a switch that can automatically determine their VLAN assignments. Dynamic VLAN functions are based on MAC addresses, logical addressing, or protocol type of the data packets |
| Dynamic VLAN Benefits | less administration within the wiring closet when a user is added or moved and centralized notification when an unrecognized user is added to the network |
| Flat network | When no routers are placed between the switches, broadcasts (Layer 2 transmissions) are sent to every switched port |
| Flat network advantages & disadvantages | 1. provide both low-latency and high-throughput performance and it is easy to administer; 2. increases vulnerability to broadcast traffic across all switches, ports, backbone links, and users. |
| Broadcast Domain | The set of all devices that will receive broadcast frames originating from any device within the set. Broadcast domains are typically bounded by routers because routers do not forward broadcast frames |
| VLANs & Network Security | One cost-effective and easy administrative technique to increase security is to segment the network into multiple broadcast groups that allows the network manager to: |
| Collision Domain | In Ethernet, the network area within which frames that have collided are propagated. Repeaters and hubs propagate collisions; LAN switches, bridges and routers do not |
| Which layers do VLANs operate at? | VLANs work at Layer 2 and Layer 3 of the OSI reference model |
| How do you logically group users in VLANs? | frame filtering, frame tagging, and frame identification. |
