Are You Smarter Than a CCENT? Transport Layer

May 21, 2017 at 11:43 am

Here is a query from a current project – enjoy!

  1. You are examining a packet capture from your local network. What two determinations can you make from this output? (Choose 2)

100-105a. This is a UDP packet
b. This is a TCP packet
c. The target destination is FTP
d. The target destination is HTTP

Be sure to enter your answer in the comments are here at the blog. I will post the answer in a day or so!

My Next Book! Mastering the CCIE Evolving Technologies Section

April 28, 2017 at 8:20 pm

CCIE Evolving Technologies

You asked for it! You got it! Terry Vinson and I are putting together an e-book (and print) for you to master this section in most of the CCIE Written Exams. I have received more questions about this section of the written exams than any other topic (pretty much ever!)

Since Cisco Systems announced these new additions to the already brutally difficult written exams, students have been in a bit of a panic about finding the scarce training materials to address these topics.

Our text follows the current blueprint letter for letter. There are plenty of practice questions to build your confidence, and no topic is left unexplored.

Thanks to Amazon.com, we are able to bring this product to you for a price that makes sense – the e-book version will be just $9.99!

Note this text arrives quickly – our current publication date is May 31, 2017!

Check Out My Other Books! 

CCIE Evolving Technologies – Cloud Performance and Reliability

February 8, 2017 at 2:39 pm

Evolving

Here is my latest installment in the complimentary CCIE Evolving Technologies training that all candidates must master for any CCIE written exam.

CCIE Evolving Technologies – Cloud Performance

Cloud technologies can cause great enhancements in the performance of your enterprise IT needs, or, they can cause nightmares. Understand that due to virtualization, contention for cloud resources, if not properly managed (especially in multitenant environments) can make performance unacceptable.

There are numerous public cloud providers who sell cloud server instances, typically by the hour and priced based on the memory (DRAM) size of the instance. In such an environment, an 8 Gbyte instance might cost roughly eight times as much as a 1 Gbyte instance. Other resources, such as CPUs, are scaled and priced according to the memory size.

The result can be a consistent price/performance ratio, with some discounts to encourage the use of larger systems. Some providers allow you to pay a premium for a larger allotment of CPU resources (a “high-CPU instance”). Other resource usage may also be monetized, such as network throughput and storage.

Cloud technologies provide the unique ability for dynamic capacity allocation. Companies can increase server instances as needed, in reaction to real load. This can also be done automatically via the cloud API, based on metrics from performance monitoring software. A small business or start-up can grow from a single small instance to thousands, without a detailed capacity planning study as would be expected in enterprise environments.

Storage in the cloud can be an area of concern since when compared to local disk, performance can vary considerably. As a result, some storage services allow an IOPS rate to be purchased when reliable performance is desired.

Fortunately, OS virtualization features great enhancements in performance. Have you ever virtualized Windows, providing the bare minimum of required RAM and witnessed it outperform tradition systems installs with dramatically more RAM. This is an excellent aspect of cloud computing.

CCIE Evolving Technologies – Cloud Reliability

While cloud performance is quite tricky and can be a risk or great reward, reliability thanks to the cloud, tends to be a much more reward based proposition.

Contingency planning efforts for continuity of operations and disaster recovery are concerned with designing and implementing cloud architectures that provide run-time reliability, operational resiliency, and automated recovery when interruptions are encountered, regardless of origin.

The technologies features in IT clouds today help ensure this and include:

  • Resource Pooling
  • Resource Reservation
  • Hypervisor Clustering
  • Redundant Storage

While these technologies address basic failover and availability demands, more specialized and complex approaches include:

  • Dynamic Failure Detection and Recovery
  • Zero Downtime

These help establish resilient cloud architectures that act as pillars for enterprise cloud solutions.

CCENT ICND1 100-105 Exam Cram Premium Edition and Practice Test