Hello my friend,
A year ago, on 5. June 2016 I’ve posted my first article about joint operation about Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR with explanation how to connect two virtual routers on your laptop. Since then 33 articles were posted. Let’s make a quick recap what we have discussed so far.
33 articles over 1 year means that the article is being posted roughly in 1,5-2 weeks.
That time I was newbie in Nokia (Alcatel-Lucent) SR OS world, though I was already CCIE #49412 in Cisco. It was interesting for me discover new world
- We started with explanation, how to connect Nokia (Alcatel-Lucent) VSR to Cisco IOS XR. Both routers are working in different virtualization environments (VSR in KVM and XRv in VMWare)
- Then I’ve spotted that Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR are very similar in terms of configuration and CLI logic. So I’ve provided brief comparison of both CLIs.
- Even before getting into details of protocols configuration, it’s necessary to understand how to deal with IPv6 as nowadays it’s a must for Service Provider networks.
- The next step of the journey into the world of interoperability between Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR was taken into direction of logging, as it’s necessary upon building and troubleshooting the network.
- For some days I had a problem with my laptop and was not able to configure anything so I decided to write more conceptual article explaining the structure of the service provider routers and naming conception used by different vendors.
- My laptop was back to normal operation and I continued CLI trip by describing VLAN trunking between Nokia (Alcatel-Lucent) VSR and Cisco IOS XR. Though being easy this information is somehow hidden in the basic course Nokia (Alcatel-Lucent) NRS I.
At this point we have covered the most basic things that are necessary to prepare router for its main task that is routing. Up now I’ve started dealing with configuration of the routing protocols
- The first routing protocol that I covered for interoperability case was OSPFv2 for IPv4 addressing. You can recall, there are some deviation in default parameters that must be solved, before you can get OSPF working between Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR.
- What’s about IPv6 routing protocols? OSPFv3 solves this problem for both vendors, meaning that from this point you can get working network based on Nokia and Cisco both for IPv4 and IPv6 addressing. Well done!
- If you don’t like OSPF, it’s OK. You can build network using ISIS, which covers IPv4 and IPv6 routing simultaneously.
- The next very important point that influences operation and performance in the network regardless of the vendor is MTU. There is different approach in Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR how to deal with it.
- Adding some security (and policy-based routing) is good option for further exploration, what adds us additional tools for our networking.
- The third major pillar (if we consider OSPFv2/OSPFv3 as a single one) in the routing world is BGP. This is something, what is used for building the Internet, and as we speak about service provider networks, we can’t pass it by.
Pure routing topics are closed, so now we have understanding how to route the traffic in our networks. This is good, but for sure not sufficient into modern world. We need much more. Yes, I’m speaking about MPLS transport.
- As usual we start with something simple. The first MPLS techonology that I covered for Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR was LDP. Here I found some new insights for me, like LDP for IPv6 for example.
- Stepping aside from MPLS we’ve shown how to make process of the configuration more robust and safe (thanks to my friend from Nokia Greg Hankins).
- And back to MPLS again. Another MPLS transport technology is BGP labeled unicast (BGP-LU), which is used for seamless MPLS and Inter-AS VPN Option C. We saw how it’s configured in Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR.
- One of the most complex though the most flexible and useful MPLS technologies is MPLS traffic engineering based on RSVP. Fast convergence, intra-AS/inter-AS traffic engineering and many other things – that is RSVP-TE!
- And till the recent days RSVP-TE was the best technology in MPLS world. But the progress doesn’t stay, so the new technology was developed that is Segment routing (or SPRING). Being developed by Cisco it’s RFC now and is used widely in other vendors including Nokia (Alcatel-Lucent).
For riders of MPLS transport are with us, so we can raise our eyes to the next level, which is MPLS services.
- The first MPLS service is the easiest in terms of configuration and its logic. It’s just a pipe that provides L2 connectivity between two points in the network without even looking into traffic. I’m speaking about VPWS that is signalled either by LDP or BGP, we configure both of them.
- Connectivity of two points is good but not enough in many cases. If you need multipoint connectivity (you network is just one big Ethernet switch), you need to use VPLS that can be also LDP and BGP signaled in Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR.
- As I’ve already said in SPRING, progress continuously brings something new. PBB-EVPN is the most scalable L2 VPN solution that can be used for multipoint connectivity in your network. And it works between Nokia and Cisco, which is just fantastic.
- Besides L2 MPLS VPNs, we have also L3 MPLS VPNs, which are officially called BGP/MPLS IP VPNs. So we cover how to build it in joint environment. This feature is so useful and important that it’s de fact standard of building service provider networks.
- Though the next article could be related to MPLS transport, I write it after MPLS services and refer it to service. I’m speaking about seamless MPLS (or unified MPLS), which is used in high scale MPLS environment.
Again, thanks to Greg Hankins, who shew me Ansible. Some articles were also posted regarding network automation using this tool.
- Initial article shows how to install Ansible at your Linux workstation, configure it and connect it to your Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR routers.
- The second article shows how to create advanced scripts (called playbooks) to make automation using Ansible really useful. In this case useful means adopted to each device that is parametrization of the scripts.
All other topics can be composed in on big chapter that is called advanced MPLS services, because they deal with MPLS transport or services and they are not necessary for the major part of the deployments. Though they can bring benefits if they are used correctly.
- BGP/MPLS IP VPN inter-AS option B. This type of VPN is used if you connect two service provider networks and what to provide end-to-end MPLS VPN for customers.
- BGP/MPLS IP VPN inter-AS option C is the most scalable though the most complex as you need to negotiate a lot of network parameters between two service provides’ networks.
- Interoperability fun between Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR upon configuration of IP fast reroute (IP FRR) and MPLS/LDP FRR. Not everything works, so you need to be aware of.
- Segment routing (SPRING) brings its own FRR technology that is TI-LFA and it works well in the multivendor network with Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR.
- Very often you want to used different MPLS paths or even different MPLS transport technologies for different MPLS Services. Nokia and Cisco have different approaches to achieve this, so we show that is necessary to know for you to bring your design to reality.
- BNG, BRAS… There are some others name that is used to terminate customer sessions (regardless they used PPPoE or IPoE). What is common is the stitching of L2 and L3 part of this service at your BNG, what is called PWHE if you use IP/MPLS access.
- PWHE is used for customers that by default shouldn’t talk to each other, but if we speak about data center environment (with MPLS data plane) or LTE access (S1/X2 interfaces), or something else, we need to have big L2 domain stitched to L3 somewhere as well. That is routed VPLS both in Cisco IOS XR and Nokia (Alcatel-Lucent) SR OS.
There are two more articles that are not related directly to any previous chapter.
- In the beginning of the list there was article explaining structure of service provider router. But we didn’t talk about virtual routers. We do it now by adding modules to virtual routers in Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR.
- The most recent article touches the overall structure of route policies, how they are configured and used in the networks.
For now, that’s all. I hope in the new year there will be a lot of new articles regarding joint operation of Nokia (Alcatel-Lucent) SR OS and Cisco IOS XR, as there are a lot of questions that I haven’t covered so far.
Stay tuned, stay with us.
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Best regards,
Anton Karneliuk