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April 2016 CCDE Bootcamp

CCDE Bootcamp – This is an Online Cisco CCDE exam preparation training.

Probably you all know the success of Orhan Ergun’s CCDE Bootcamps and how it has been helping so many engineer become a better network engineer/designer. If you don’t know, please just take a tour on the website. Check the Success Stories, Why Orhan and the Sample Videos.

Let’s continue to our journey with the April 2016 CCDE class.

Please note that, there is a 20% discount for the early registrations. February 15 is the last day.

Come and learn the network design from the best !

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Orhan Ergun July 2015 CCDE Training

Attention CCDE Practical & CCIE Career Track Candidates!

I am pleased to announce that my next online WebEx CCDE live stream training will begin on July 20th, 2015.
This class will be recorded and distributed to all students for their future review.

This class will not only help CCDE students pass their practical exam, but also aid CCIE candidates fill in knowledge gaps and further their understand of technical concepts and theory.

Course will be delivered over a one month period, 3 days a week, 3 hours per session.
This is to allow the student to digest the information as well as work through the topics presented.
This approach not only aids in your retention of the information presented, but is also HIGHLY cost effective since ancillary training costs (travel and lodging) are nil.
Students may also take future CCDE offerings free of charge until they pass their CCDE.

To find out what previous students are saying about this course (click here).
Success stories of previous students as well as their thoughts on my training versus others (click here).
To watch a sample video module (click here).

What is covered ?

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CCIE R&S,SP,Wireless,Collaboration,Datacenter,Security Preparation Recommendations

CCIEOrhan Ergun and Neil Moore talked about CCIE Preparation on the packetpushers podcast.

Neil Moore is only 8xCCIE in the world and well known geek and HP fellow.

 

 

  • Which exam is the hardest ?
  • What are their advises ?
  • Which certification should be received first, what should be the order ?
  • CCIE vs CCDE ?
  • What is the specific preparation methodology for each certification ?

If you liked the podcast and found it helpful, please share your thoughts and additional questions in the comment , I and Neil will be happy to answer you.

Click here to listen.

Orhan Ergun 2 Comments

MPLS Layer 2 and Layer 3 VPN

RFC 2547 defines standard MPLS VPN to carry customer prefixes over the MPLS backbone.

In February 2006 RFC 4364 was published for Inter AS VPNs which is known as Multi AS VPNs. RFC 4364 obsoleted RFC 2547 and  defined many other applications for MPLS VPNs such as CSC which is also known as Carrier Supporting Carrier with the Cisco terminology and Carrier of Carrier with the Juniper definition.

With basic Layer 3 MPLS VPN , Enterprise customers can carry their prefixes from multiple sites over SP backbone . It is multi point to multipoint connection. With the ATOM based MPLS solution which is Cisco’s E-Line solution , customer sites are connected as point to point and with VPLS multipoint to multipoint.

Basic difference with the VPLS and IP/VPN from customer point of view , with VPLS all attached sites share the same L3 network.Service Provider acts as a big switch for the customer. IP/MPLS VPNs use different IP address at each site.

With the IP/VPN also known as BGP or L3 VPN , customer runs IP routing protocol or static route with the Service provider and Customer equipment which is known as CE don’t see other CE as connected like in VPLS or ATOM based MPLS.

Depending on expectations of the customer from the Service Provider , for the MPLS L3/VPN case, customer can run any of the IGP routing protocols including EIGRP, OSPF, IS-IS , BGP or static route. You may want to talk with your Service Provider before you decide since some Service Providers don’t service every routing protocols. Most of them if not all supports BGP.

If customer wants very granular policy control, dual homed site connectivity, and customer network stuff well trained , best choice would be BGP.

In the past fast convergence was an issue with BGP and maybe still with the vanilla BGP configuration, recent enhancements allow BGP to converge super fast thanks to BGP Fast Reroute Mechanism which is BGP PIC.

All IGP protocol’s metric information can be carried over SP MPLS backbone end to end. In this case SP core behaves differently. For OSPF there is Superbackbone and for ISIS there is L3 backbone concepts. This is out of the scope of this post so I will not explain further.But if you want to learn and interested please comment, so I definitely write about them.

One another caveat for PE-CE protocol , for almost all protocol , if customer has backdoor link to another customer site, loop or suboptimal path usage may occur. We prefer generally MPLS link when it is necessary to have low latency , secure , reliable connection compare to Internet based option.

If customer has backup Internet link (Not MPLS but maybe DSL, 3G/LTE, Satellite,Microwave, Cable) and its requirement is low latency , predictable delay variation which is called as jitter , reliable and secure ( Relative ) connection, probably wants to use MPLS connection as primary and Internet connection as a backup although LTE is much cheaper and provides very high bandwidth nowadays and started to take its place as a primary connection on some networks or part of the network such as remote offices.