ISP Network Engineer Interviewing Tips

hbk

Hey all,

There's this Network Engineering I position opening for a rather big ISP. I know there has been a couple of other interviewing threads out there but none has been able to answer some of my uncertainties, or maybe I'm just a bit nervous and need direct advice

Anyways, what are some advice you guys can offer for this Network Engineer I ISP position as far as study materials, and preparing for this interview in general? Any tips/advice is appreciated, thanks.

HBK

Essendon

For such a position, they are generally after people who can take some abuse from customers, think quickly, perform basic troubleshooting and escalate as needed. They'll ask you stuff on the lines of what would you do if an irate customer with Internet issues calls up. You should go something like this - I'd listen to the customer carefully, understand the problem and say - Sure, this is something I can help you with, and then begin your troubleshooting. You should say, I'd ask them if the Internet has ever worked before, what were they doing when the issue happened, meaning yiu need to get as much info out of them as possible. Test their modem connectivity, get them to check the lights on the modem, do a ping to the modem, ping google.com, do a trace route. Give them the warm fuzzy feeling!

DANMOH009

Is it working on the ISP's network? or a customer Facing/Help-desk role? If its a Customer facing, then a lot of it i reckon would be getting the end user connected, Therefore a few local checks maybe knowledge of the technology they use ADSL/VDSL/VOIP etc.. (nothing too much just understand what they are). If its working on the ISPs own network then a lot of companies use MPLS/BGP, again these are just guidelines though its best to tear the job description apart.

networker050184

Same as any other interview really. Read the job description and be ready for questions on anything listed. The biggest thing though is to make sure you can speak to anything on your resume in depth. When you interview people know you don't know everything, but if you say you know something then you better know it. IMO it's better to spend your time reviewing what you already know rather than trying to learn new things. Maybe do a quick google search on the things you are unfamiliar with just so you have an overview.

hbk

Thanks for all the input so far. I'm not quite sure which side it'll be. So maybe study the routing/switching protocols, mpls, frame relay?
I'm not taking this interview lightly, I'm making sure I'll be ready to explain everything on my resume as they'll be fair game questions.
And yea, I kind of think it's pointless to try and learn new things....I'd rather just master what I know rather than trying to get a so-so understanding of everything.

Somnipotent

A Network Engineer I position, depending on the role you will be playing, will require you a thorough understanding of CCNA level knowledge and mastery of basic troubleshooting techniques. What's your experience with telecom? Major ISPs will take into consideration people who are well grounded on telecom technologies, so if you know the difference between a DS1 and an OC3, and what BPV and ESPs mean, you're golden. If you don't, not sweat either, just make sure you know what's expected of you. Customer service skills are essential in the ISP world. Sometimes you will be working directly with the customer and you will be the face of the company on that regard.

Ideally the interview process, as I have been involved in, will be double or triple pronged. You will be asked questions on what's listed on your resume and be prepared to back up what you list. If you're a CCNA, expect to be grilled on a CCNA level. 99% of the time there will be a technical panel to assess your skills. Depending on the position you may be asked basic stuff like what's the difference between OSPF and EIGRP, subnetting questions, and physical layer stuff. If the panel wants to have fun with you, they'll draw up a diagram and ask you to whiteboard your troubleshooting methodology. Expect to be hammered. If you know your stuff, no sweat. If you don't, bring a towel, you'll be sweating. More often than not, if you survive, you'll be asked personality, situational questions. Answers should show that you're a team player, with the ability to learn and adapt, face challenges and know how to escalate issues when you can't fix 'em. Getting in with an ISP is a great experience because not very many Network Engineers get to see that side of the house. You will learn and you will grow exponentially. Good luck. PM me if you have questions or need further coaching. I work for Verizon

hbk

Thanks for the advice Somnipotent.
I don't have too much of a background working at a teleco
I have a pretty solid understanding of routing/switching, plus I've had some experience with dealing with customers and those sort of things. Not where I want to be as far as being with the company I'd like but I feel that this opportunity would be a great one for me to get to learn their technologies and advance my knowledge.
What kind of projects do they usually throw at CCNA level engineers?

networker050184

It depends on the job function. Is it internal, customer facing, troubleshooting role, turn up, surveillance, grooms? Kind of hard to give you any input with more info on the specific role. A lot of places call almost every role an engineer so that doesn't really help much either.

Somnipotent

No experience with telecom isn't too big of a deal. Since your title is NETWORK ENGINEER I a lot of that layer 1 stuff will be handled by a separate group. Having worked with large ISPs like Sprint and Verizon, I know first hand they offload the physical layer to a separate team. Make sure know what team you're applying for if that's the case. If it does not state, this is a question to ask during the interview. If you're working on service delivery, you'll more than likely be working on the PE devices, better know your BGP!!!. You could be part of a team that works on the core/backbone routers (IS-IS, wink wink, would be good to know if this was the case). If you're in operations or managed services, you'll be working with the devices at the customer prem or at colocated facilities. Mostly CE routers, sometimes switches, load balancers, firewalls, waas appliances, etc. This side of the house touches everything! QoS, dynamic/static routing, security... the works. With an ISP there are many facets and many types of "network engineers" and you will see that. I also highly doubt you'll be doing much surveillance work, ISPs usually designated NOC folk as NETWORK CONTROL TECH or NETWORK OPERATIONS TECH.

On a side note, unless you're working for Sprint Service Delivery, Juniper knowledge gives you a boost. Verizon and AT&T have more Juniper devices (they're both technology partners). I suggest, if you are serious about going the ISP route, heading over to the Juniper site, and taking their JNCIA fast track course. If you pass it, you get a 50% off voucher to take the test. It's cake if you're a CCNA.