Question: What Is A Layer 2 Interface?

What is a Layer 3 interface?

VLANs divide broadcast domains in a LAN environment.

This is known as inter-VLAN routing.

On Layer 3 switches it is accomplished by the creation of Layer 3 interfaces (SVIs).

SVI or VLAN interface, is a virtual routed interface that connects a VLAN on the device to the Layer 3 router engine on the same device..

What is Layer 2 and Layer 3 networks?

Generally speaking, Layer 2 is a broadcast Media Access Control (MAC) MAC level network, while Layer 3 is a segmented routing over internet protocol (IP) network. To better understand both layers, let’s dig a little deeper into the OSI model.

What is a physical interface?

Physical interfaces consist of a software driver and a connector into which you connect network media, such as an Ethernet cable. … Logical interfaces are configured onto existing physical interfaces, usually for adding addresses and creating tunnel endpoints on the physical interfaces.

What is firewall transparent mode?

Transparent mode converts the firewall device from its default layer 3 route mode to what is essentially a layer 2 bridge.

What is Layer 2 address?

The layer 2 address is a physical address. It pertains to the actual hardware interface (NIC) in the computer. A computer can have any number of layer 3 addresses but it will only have 1 layer 2 address per LAN interface. At layer 3, the data is addressed to the host that the data is destined for.

How does a Layer 2 firewall work?

A Layer 2 transparent firewall operates on bridged packets and is enabled on a pair of locally-switched Ethernet ports. Embedded IP packets forwarded through these ports are inspected similar to normal IP packets in a routing network.

Which two items can a logical interface represent?

A LIF (logical interface) is an IP address with associated characteristics, such as a role, a home port, a home node, a routing group, a list of ports to fail over to, and a firewall policy.

What is a logical interface called in the Junos OS?

The Junos OS automatically configures one loopback interface (lo0). The logical interface lo0. 16383 is a nonconfigurable interface for router control traffic.

What is Layer 4 firewall?

The layer 4 firewall is a device that can look at all the protocol headers upto the transport layer and not the headers above that layer.

Is VLAN a Layer 2?

VLANs are data link layer (OSI layer 2) constructs, analogous to Internet Protocol (IP) subnets, which are network layer (OSI layer 3) constructs.

Does Layer 3 switch have IP address?

Simply put, a layer 3 switch combines the functionality of a switch and a router. It acts as a switch to connect devices that are on the same subnet or virtual LAN at lightning speeds and has IP routing intelligence built into it to double up as a router.

What is a logical interface?

A logical interface (LIF) Is a software entity consisting of an IP address that is associated with a number of attributes such as a role, a home port, a firewall policy, a home node, a routing group and a list of ports for failover purposes. Logical interfaces are created through configuration.

How does a transparent firewall work?

A transparent firewall acts like a “stealth firewall” and it is actually a Layer 2 firewall. In order to implement this, the connection of the security equipment is made to same network on both the internal and external ports. … Transparent firewall mode supports outside interface and an inside interface.

Can we assign IP address to layer 2 switch?

Contrary to Router/Firewall configuration, Layer 2 Switch has ports configured as Layer 2 which can’t be given an IP address, instead SVI (Switched Virtual Interface) needs to be assigned an IP address. Switch is assigned IP address to manage it via Telnet or SSH services.

What layer is MPLS?

layer 2.5MPLS is considered a layer 2.5 networking protocol. Layer 2 carries IP packets over simple LANs or point-to-point WANs, while layer 3 uses internet-wide addressing and routing using IP protocols. MPLS sits in between, with additional features for data transport across the network.

Is firewall a layer 2 or 3?

Generally, firewalls are used to protect your internal/private LAN from the Internet. A firewall generally works at layer 3 and 4 of the OSI model. Layer 3 is the Network Layer where IP works and Layer 4 is the Transport Layer, where TCP and UDP function.

Can a layer 3 switch Do NAT?

I would like to use a Layer 3 switch as my gateway between my LAN and the ISP. I discovered that much as you can configure an IP address on the physical interface of a switch when it is running on Layer 3 mode, you cannot apply command of ” IP nat inside” or “IP nat outside” on the Interface configuration mode.

How do I know if my switch is layer 2 or 3?

These switches will move traffic to specific ports based on source and destination MAC addresses (link layer). When switches allow for IP-based routing, VLANs, etc, they have layer 3 capabilities, e.g. routing. Almost all “smart” switches and all “managed” switches are layer 3. All “unmanaged” switches are layer 2.