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Barracuda CloudGen Firewall



Measure of the difference in packet delay, that is, the difference in the space between packet arrival times. Jitter can be remedied somewhat with a jitter buffer.

  • Also known as: JavaScript Object Notation

An open, text-based data exchange format (like XML), that is human-readable and platform-independent. Data formatted according to the JSON standard is lightweight and can be parsed by JavaScript implementations.


A kilobit.


A network authentication protocol, designed to provide strong authentication for client/server applications by using secret-key cryptography. Available for free from the Massachusetts Institute of Technology, also available in commercial products.

  • Also known as: Kernel-Based Virtual Machine

A virtualization infrastructure for the Linux kernel that turns it into a hypervisor. KVM requires a processor with hardware virtualization extension.

  • Also known as: Layer 2 Tunneling Protocol

A network protocol that supports tunneling of layer 2 frames between two networks over the Internet.


Delay in transmission time that occurs while information remains in a device's buffered memory (such as a bridge or router) before it can be sent along its path.

Launch Configuration

AWS template that an Auto Scaling group uses to launch EC2 instances. Contains AMI, instance type, key pair, security groups, and block device mapping.

layer 4

The transport layer from the ISO/OSI model, which provides end-to-end or host-to-host communication services for applications within a layered architecture of network components and protocols.

Layer 7 Application Control

A legacy feature of the Barracuda NG Firewall. Barracuda Networks recommends using the new Application Control in Barracuda NextGen Firewall instead.

  • Also known as: Lightweight Directory Access Protocol

Application protocol used to manage and access the distributed directory information service.

  • Also known as: LDAP over SSL, Secure LDAP

Connection protocol used between application and Network Directory or Domain Controller. LDAPS communication is encrypted and secure.


Latest maintenance release for the previous major firmware version.


A universal lossless data compression algorithm

link aggregation
  • Also known as: 802.3ad Link Aggregation, LAG

Operating mode for Ethernet bundles that uses the LACPDU protocol to negotiate automatic bundling links.

link balancing

Dynamically balancing traffic across multiple Internet Service Provider (ISP) links to ensure Internet continuity and availability, even during ISP outages.

link state routing
  • Also known as: Open Shortest Path First

A routing protocol that takes link loading and bandwidth when selecting between alternate routes. Example: OSPF.


Method of storing or transmitting data in which the least significant bit or byte is presented first. Compare with big-endian.

local authentication database

Built-in user database for local authentication on the firewall.

local bridge

Bridge that directly interconnects networks in the same geographic area.

Log Viewer

  • Also known as: link-state advertisement, link state advertisement

Broadcast packet used by link-state protocols that contains information about neighbors and path costs. Used by the receiving routers to maintain their routing tables.