Chapter 23 Configuring QoS

Configuring QoS

2.Typically, the maximum size is 1538 bytes, or 1542 bytes for tagged Ethernet. If you allow jumbo frames (if supported for your platform), then the packet size might be larger.

3.The delay depends on your application. For example, to control jitter for VoIP, you should use 20 ms.

Configuring the Standard Priority Queue for an Interface

If you enable standard priority queuing for traffic on a physical interface, then you need to also create the priority queue on each interface. Each physical interface uses two queues: one for priority traffic, and the other for all other traffic. For the other traffic, you can optionally configure policing.

Note The standard priority queue is not required for hierarchical priority queuing with traffic shaping; see the “Information About Priority Queuing” section on page 23-3for more information.

Restrictions

•(ASASM) The ASASM does not support priority queuing.

•(ASA 5580) You cannot create a standard priority queue for a Ten Gigabit Ethernet interface. Note: For the ASA 5585-X, standard priority queuing is supported on a Ten Gigabit Interface.

•(ASA 5512-X through ASA 5555-X) Priority queuing is not supported on the Management 0/0 interface.

Detailed Steps

Step 1 Go to Configuration > Device Management > Advanced > Priority Queue, and click Add.

The Add Priority Queue dialog box displays.

Step 2 From the Interface drop-down list, choose the physical interface name on which you want to enable the priority queue, or for the ASA 5505 or ASASM, the VLAN interface name.

Step 3 To change the size of the priority queues, in the Queue Limit field, enter the number of average, 256-byte packets that the specified interface can transmit in a 500-ms interval.

A packet that stays more than 500 ms in a network node might trigger a timeout in the end-to-end application. Such a packet can be discarded in each network node.

Because queues are not of infinite size, they can fill and overflow. When a queue is full, any additional packets cannot get into the queue and are dropped (called tail drop). To avoid having the queue fill up, you can use this option to increase the queue buffer size.

The upper limit of the range of values for this option is determined dynamically at run time. The key determinants are the memory needed to support the queues and the memory available on the device.

The Queue Limit that you specify affects both the higher priority low-latency queue and the best effort queue.

Step 4 To specify the depth of the priority queues, in the Transmission Ring Limit field, enter the number of maximum 1550-byte packets that the specified interface can transmit in a 10-ms interval.

This setting guarantees that the hardware-based transmit ring imposes no more than 10-ms of extra latency for a high-priority packet.

Cisco ASA Series Firewall ASDM Configuration Guide

23-8

Page 547 Page 549
Page 548
Image 548
Cisco Systems ASA 5555-X, ASA 5505, ASA 5545-X, ASA 5585-X Configuring the Standard Priority Queue for an Interface, 23-8
Page 547 Page 549

ASA Services Module, ASA 5555-X, ASA 5545-X, ASA 5585-X, ASA 5580 specifications

Cisco Systems has long been a leader in the field of network security, and its Adaptive Security Appliance (ASA) series is a testament to this expertise. Within the ASA lineup, models such as the ASA 5505, ASA 5580, ASA 5585-X, ASA 5545-X, and ASA 5555-X stand out for their unique features, capabilities, and technological advancements.

The Cisco ASA 5505 is designed for small businesses or branch offices. It provides essential security features such as firewall protection, flexible VPN capabilities, and intrusion prevention. The ASA 5505 supports a user-friendly interface, allowing for straightforward management. Its built-in threat detection and prevention tools provide a layered defense, and with scalability in mind, it can accommodate various expansion options as organizational needs grow.

Moving up the line, the ASA 5580 delivers greater throughput and advanced security features. This model is suited for medium to large enterprises that require robust protection against increasingly sophisticated threats. Its multi-core architecture allows it to manage high volumes of traffic seamlessly while maintaining excellent performance levels. The ASA 5580 also supports application-layer security and customizable access policies, making it highly adaptable to diverse security environments.

The ASA 5585-X further enhances Cisco's security offerings with advanced malware protection and extensive security intelligence capabilities. It incorporates next-generation firewall features, including context-aware security, and supports advanced threat detection technologies. This model is ideal for large enterprises or data centers that prioritize security while ensuring uninterrupted network performance and availability.

For enterprises requiring a balance of performance and security, the ASA 5545-X presents a compelling option. This model features scalable performance metrics, high availability, and integrated advanced threat protection. Coupled with advanced endpoint protection and detailed monitoring capabilities, the ASA 5545-X enables organizations to manage their security posture effectively.

Lastly, the ASA 5555-X blends cutting-edge technologies with strong security infrastructures. It boasts high throughput and the ability to execute deep packet inspections. Its sophisticated architecture supports threat intelligence feeds that provide real-time security updates, making it a powerful tool against modern threats.

Each of these Cisco ASA models brings specific advantages to varied environments. Their integrative capabilities enable businesses to enhance their security postures while benefiting from seamless scalability and management. As cybersecurity threats evolve, these advanced appliances play a vital role in protecting valuable digital assets.
Top Page Image Contents