So far we’ve explored some very cool features of CEF and the attributes we can push into the FIB to identify certain kinds of traffic. We can color the prefixes in the RIB and FIB with a particular IP-Precedence, QoS-group or traffic_index and we can then perform traffic monitoring, shaping and policing and packet marking […]
The post Secret CEF Attributes, Part 5 appeared first on Packet Pushers Podcast and was written by Dan Massameno.
The Management Challenges of SDN
Really, when we talk about SDN in the WAN, all we’re talking about is separating the control plane (which tells data where to go) from the data plane (which forwards traffic to the next node). We’ll still have physical routers and other infrastructure, but they’ll become “commodity forwarding devices” with the control plan intelligence residing in a server – the SDN controller. This enables us to create virtual network overlays and functions.
Where this can be a challenge is not so much in figuring out how to integrate it into your network but the lack of widely accepted standards for SDN. Certainly, the Open Networking Foundation is developing one, but it’s yet to see full adoption. And without standards for SDN, it will be difficult to build systems. Now the ONF and other consortia and standards bodies such as the IETF are making progress on this issue – and Packet Design will be part of the process by which progress is made – but until standards are fully established, SDN may be limited only to those companies willing to spend the massive amount of time Continue reading
The QinQ feature (802.1q over 802.1q), also known as Stacked VLAN or VLAN over VLAN, supports the utilization of two 802.1q tags on the same frame Ethernet for VLAN over VLAN traffic – without altering the original TAG.
For the customer perspective it is like the Service Provider has extended the cable or fiber between 2 points. From the Service Provider perspective, it doesn’t matter if the customer is sending a frame ethernet with or without TAG 802.1q, because it will add one more TAG to the header and remove on edge device just the last insert tag.
In a nutshell, the inbound interface configured with QinQ, will add a 802.1q TAG to the frame, even in case if the VLANs were tagged, however on the outbound port, only the last TAG added is removed, keeping the TAG 802.q inserted by the client.
Configuring
With the example above, we shall configure both Switches A and B with one VLAN for each client and configure the customer-connected-interfaces, such as “qinq enable”. As a detail, notice that is important to disable the STP on each interface for the BPDU issues, so the BPDUs will not interfere Continue reading
Enterprises are still a complex mix of legacy and newer cloud applications, yet smart use of universal SDN-based cloud networks is the great equalizer in bringing enterprises and the new applications of the cloud together. Evolutionary migration strategies from a mainframe to a client-server architecture can also be applied to the next phase of cloud and virtual age networking. To appreciate how they apply, one must better understand the diverse definitions of SDN, and its true applicability in next generation networks. Let’s review some of the terminology often used and confused in our industry.
Overlay SDN: The most visibly promoted controller for SDN overlays today is VMware’s NSX (Microsoft System Center, Juniper Contrail and Nuage Networks may also fall into this category). Some networking features and functions are moved into overlays to control the data, flow or forwarding path. This includes:
1. Software overlays to shift management functions from the control plane of the network to servers
2. Specific use-cases such as server virtualization, L4-L7 load balancing, security, Openflow etc.
Functional controllers leverage existing physical networks and apply features and functions such as provisioning that can be used via abstraction, APIs, a CLI and limited scripting.
Underlay SDN: Controllers do Continue reading
SDN Management Challenges of Wireless Carriers
Our CTO Cengiz Alaettinoglu recently published an article in RCR Wireless’ Reality Check column titled “Stumbling Block: SDN Management Challenges.” He discusses three SDN applications that are particularly valuable for wireless carriers: bandwidth calendaring, demand placement, and rapid provisioning. In fact, Cengiz says that rapid provisioning “…is indeed surfacing as the killer SDN application for carriers beyond the data center.”
However, these applications cannot be used successfully in SDN environments until the industry solves numerous management challenges. Traditional, manual management methods and processes cannot keep up in a programmable, automated network environment. As a result, the human operator loses visibility and control, making it difficult to understand how to plan for the rollout of new applications and services. Lack of oversight creates a sort of wild west environment without anyone or anything governing whether or not these programmatic changes should be made.
Cengiz is currently working on a prototype of a Network Access Broker that will verify if the WAN can handle the traffic demands of SDN applications without impacting other applications adversely. You can read more about what he says Continue reading
At Networking Field Day 7, the delegates were treated to vendor demonstrations that challenged our thinking about the future of networking. Perhaps the industry is not agreed on just how we’ll implement and operate our networks in the coming years, but one thing is for certain. The landscape will be different. In this and the […]
The post Show 182 – The Future of Networking Part 1 As Inspired By #NFD7 appeared first on Packet Pushers Podcast and was written by Ethan Banks.
Introduction NAT is bad, it breaks end to end connectivity. It’s misused as a security tool. Using NAT kills kittens. Yes yes, we all know that. That doesn’t mean that there aren’t valid use cases for NAT and when NAT can save the day. What was the problem? Imagine that you have a device that […]
The post NAT saves the day! appeared first on Packet Pushers Podcast and was written by ddib.
[player] This week Andrew & Greg are joined Howard Marks whose abundance of commentary leads to a surfeit of opinions on the lack of anything happening at Mobile World Congress. Show Notes MWC – Wearable computing on the rise? Netflix and Comcast: Is this the first Network Neutrality domino to fall? Frontier customer complaints drop […]
The post Coffee Break – Show 4 appeared first on Packet Pushers.
This week Andrew & Greg are joined Howard Marks whose abundance of commentary leads to a surfeit of opinions on the lack of anything happening at Mobile World Congress. Show Notes MWC – Wearable computing on the rise? Netflix and Comcast: Is this the first Network Neutrality domino to fall? Frontier customer complaints drop nearly […]
The post Coffee Break – Show 4 appeared first on Packet Pushers Podcast and was written by Greg Ferro.
