What does a switch do when a frame is received on an interface and the destination hardware
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Q: What are the typical three different categories of VPNs? Answer The following are the different types of VPNs : PPTP ( Point to Point Tunnel protocol ) VPN : Most commonly used VPN. PPTP is a method for implementing virtual private networks. PPTP uses a control channel over TCP and a GRE tunnel operating to encapsulate PPP packets. Site-to-Site VPN : Site-to-site VPN is a type of VPN connection that is created between two separate locations. Site-to-site VPN can be intranet based or extranet based. Intranet-based site-to-site VPN is created between an organization's propriety networks, while extranet-based site-to-site VPN is used for connecting with external partner networks or an intranet. L2TP ( Layer Two Tunneling Protoco) VPN : L2TP is an extension of the Point-to-Point Tunneling Protocol (PPTP) used by an Internet service provider (ISP) to enable the operation of a virtual private network over the Internet. IPsec (Internet Protocol Security) : IPsec is a framework for a set of protocols for security at the network or packet processing layer of network communication. SSL (Secure Sockets Layer) VPN : SSL is a form of VPN that can be used with a standard Web browser. In contrast to the traditional Internet Protocol Security (IPsec) VPN, an SSL VPN does not require the installation of specialized client software on the end user's computer. MPLS (Multiprotocol Label Switching) VPN : MPLS is a protocol for speeding up and shaping network traffic flows. Hybrid VPN : A hybrid VPN combines Multiprotocol Label Switching (MPLS) and Internet protocol security (IPsec)-based VPNs. View answer Workspace Report Error Discuss When a frame arrives at a switch interface, the switch looks for the destination hardware (MAC) address in its MAC table. If the destination MAC address is found in the table, the frame is only sent out of the appropriate interface. The frame won’t be transmitted out any interface. However, if the destination MAC address isn’t listed in the MAC table, then the frame will be sent (flooded) out all active interfaces, except the interface it was received on. If a device answers the flooded frame, the MAC table is then updated with the corresponding interface. We will explain the switch forwarding process using the following example network: Host A is trying to communicate with Host B and sends a frame. The frame arrives at the switch, which looks for the destination MAC address in its MAC address table:  Since the MAC address is listed in the MAC address table, the switch forwards the frame only to the port that connected to the frame’s destination (Fa0/2 in our case). Note that, however, if the MAC address was not found, the switch would flood the frame out all other ports (Fa0/2, Fa0/3, Fa0/4), except the port the frame was received on (Fa0/1). The Host B would receive the flooded frame and respond to Host A. The switch would then receive this frame on the port Fa0/2 and place the source hardware address in its MAC address table.
What does a switch do when it receives a frame?When a switch receives a broadcast frame, the switch forwards the frame out each of the switch ports, except the ingress port where the broadcast frame was received. Each device connected to the switch receives a copy of the broadcast frame and processes it, as shown in the top broadcast domain in Figure 1-22.
What happens at the switch when unknown unicast frame comes to the switch?(b) Unknown Unicast: When a switch receives a unicast frame for a destination for which the switch has no entry in its MAC table then the switch simply broadcasts the frame through all ports. This is known as flooding.
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