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Last week I passed the exam for Ericsson’s IP Essentials certification.

Even though this is the first of several IP related certifications, DO NOT LET THE NAME MISLEAD YOU!  Being the initial certifications required on the IP path and the “essentials” in the name would lead one to believe that this is a basic level exam.  It is not!  It covers IP networking, routing protocols, QoS, and MPLS and is quite comprehensive.   Detailed and thorough knowledge of all the topic areas are required in order to pass this exam.

This certification is for Ericsson employees only and is proctored by Prometric, or via remote with Ericsson proctor physically present.

The exam is difficult in that it will ensure that you know the technical details of each topic as well as understanding of how each works.  Ericsson does have online courses and practice tests available.  However, if you study up on Q0S, for example, and you do not know all details and understand how it works it would be best to study until you do by either redoing the online course or obtaining supplemental study material.

In July 2011 I passed the exam (4A0-100) for the Alcatel-Lucent NRS-I (Network Routing Specialist I) certification.

The exam requires fundamental knowledge of IP networking and routing protocols along with basic knowledge of their 7750 Service Router and is proctored by Prometric.

ALU provides training courses for all their certification exams, but I opted for the self study route and utilized the published study guide instead – Alcatel-Lucent Scalable IP Networks Self-Study Guide.  This is the perfect study guide for this exam and I plan to keep it as I feel it is a great reference guide as well.

Finally decided to use the email notification feature in AstLinux, but it wasn’t as easy to get it going as I thought.  In theory one should just have to specify your email address for notifications in your voicemail.conf file like any other Asterisk setup and also configure your email server for whatever Linux distribution you’re using.  For AstLinux the web GUI provides a convenient way to edit both your voicemail.conf  to specify the email address for notifications of new voicemail to your voicemail box and also via the AstLinux Network tab the SMTP settings for the email host that’ll receive the email notifications and send them off to where they need to go.  I planned to use my email account with AT&T as my SMTP host, but after configuring my email setup I found that when I made a test voicemail I was not receiving any email notifications.  I looked into the log file and found indications of the trouble:

From the log I see that AstLinux uses msmtp instead of sendmail for SMTP and that it’s sending emails to my AT&T account as root instead using my email address.  I guess msmtp defaults to using root when sending email.  Reading the msmtp docs I was able to determine that one can specify the from address msmtp uses by adding the SMTP_FROM statement to my startup files.  I initially added it to the /mnt/kd/rc.conf.d/gui.network.conf file, but it did not stick.  After adding it to the /mnt/kd/rc.conf.d/user.conf file and rebooting it seems to not only remain in the file, but actually being used in the configuration of msmtp.

Entry I added to my /mnt/kd/rc.conf.d/user.conf file:

SMTP_FROM=”myemailaddr@att.net”

Log entry of successful email notification:

I also wanted to send system messaging to my syslog server, but did not see anything in the AstLinux Network GUI tab for that so added the following to my /mnt/kd/rc.conf.d/gui.network.conf file:

### Syslog
SYSLOGHOST=”172.16.0.27″

After rebooting it appears that the AstLinux setup process left it in and and I’m now seeing log messages from my AstLinux PBX being logged on my syslog server.

I’ve tried to blacklist a few annoying numbers by adding them to the AstLinux blacklist, but it didn’t seem to work.  It’s not that I’m anti-social, just seems like for some reason the wife holds me accountable for any telemarketer calls we get.  Apparently the web GUI for Astlinux does have a tab to enter numbers into the Asterisk database, but you have to do some programming in your extentions.conf file in order for calls in the dialplan to be affected.  I made the following changes to my dialplan and my test calls so far are going where they should.  There is probably a more elegant ways of doing this, but I made a context for each blacklist scenario because the contexts for incoming calls are recorded in the CDR log and so when I review the CDR I can tell if incoming calls are handled normally or blacklisted.

[vitel-inbound]
exten => 9135550000,1,GotoIf($[${DB_EXISTS(blacklist/${CALLERID(num)})} = 0]?200) ; blacklist test
exten => 9135550000,n,GotoIf($["${DB_RESULT}" = "0"]?110)
exten => 9135550000,n,GotoIf($["${DB_RESULT}" = "2"]?120)
exten => 9135550000,n,Goto(Blacklist-Zap,s,1) ; “1″ TN in blacklist database, answer and Zapateller
exten => 9135550000,110,Goto(Blacklist-Hangup,s,1) ; “0″ TN in blacklist, Hangup
exten => 9135550000,120,Goto(Blacklist-VM,s,1)  ; “2″ TN in blacklist, direct to voicemail
exten => 9135550000,200,Macro(stdexten,702,SIP/702)
exten => 9135550000,201,Goto(s,end)

[Blacklist-Zap]
exten => s,1,Answer
exten => s,2,Wait(1)
exten => s,3,Zapateller
exten => s,4,Zapateller
exten => s,5,Playback(ss-noservice)
exten => s,6,Hangup

[Blacklist-Hangup]
exten => s,1,Answer
exten => s,2,Wait(1)
exten => s,3,Hangup

[Blacklist-VM]
exten => s,1,Answer
exten => s,2,Wait(1)
exten => s,3,Voicemail(702,u)
exten => s,4,Hangup

I’ve been using Asterisk, the IP PBX software, since shortly after it came out, but for the last few years have been using AstLinux.  I like AstLinux because it’s able to run on the WRAP or Seokris hardware platforms which have no moving parts and use very little power.  These little embedded IP PBXs are great VOIP solutions for simple home use.  Because AstLinux is a slimmed down version of Asterisk it means that usually only has a basic feature set available.  However, it does have a web GUI for system and Asterisk configuration which is great for quick status and small changes, but I find myself using ssh to login and make changes via UNIX shell most of the time.

Yesterday I passed my exam for the CWTS (Certified Wireless Technology Specialist) certification.  The cert comes from the CWNP group and is primarily focused on 802.11 (wifi) specs, installation, and troubleshooting.  I got 88% for most of the subject areas expect for Radio Frequency (RF) Fundamentals which I got 100%.  Since I have a lot of RF experience as an engineer at Sprint as well as a ham radio operator I felt 100% was the least I could achieve in that area.

Last month I passed the exams for the CCNT (Certified in Convergence Network Technology) certification.  It was six exams of about 100 questions each from basic telecom, digital telecom, IP networking, and VOIP.  A very grueling ordeal to say the least.

I’m not sure if I’m going for my FCC exams next or the dreaded Cisco CCNA next…