Cost of Living in Munich???

Although Munich is the most expensive city in Germany, your salary is far above the average for similar German families - so you should be fine, unless you have exceptional spending habits.
I cannot comment on whether your salary is o.k. for your job, as I have no idea what a "CCIE engineer" is or does.
Please note that rents are very high and it is difficult to find housing in Munich. You should arrange temporary accommodation for the first months (yes, months!) during which you look for a permanent place. Regarding rent levels, please consult the officially published rent statistics ("Mietspiegel"). If you need furnished accommodation, add 50% or more to the unfurnished rent.
One "exceptional spending habit" that might apply to you is private or international schooling: If you cannot (or don't want to) send your kids to local public schools (which are free, but entirely in German language) you'll have to bear the costs of minimum EUR1000/month per kid.

Thank you for the reply Beppi. I have a plan to stay in a temporary accommodation and find the permanent one. My company offering 1.5k as a relocation package or finding a permanent accommodation. can you advise on which package i can go with?

Regarding the school, Do they provide language assistance in all public school for Non-Euro kids?  For accommodation, i prefer the 2-3 room apartment alteast with kitchen . i can buy the important stuffs initially and start furnishing the apartment slowly.

CCIE is a Cisco Certified Internetwork Expert and i do design and implementation of large scale network including datacenters. This is also my worry. i do no want to go to underpaid job. I tried to find the information onsite and everwhere median salary is 60k for network engieers. But not sure CCIE add any value in Germany or not.

My employer located nearby Riem,Munich. Do you think finding an 60-80 sq.m apartment for 1k around riem is a big deal?

€1.5k will not get you far for initial expenses: The rental deposit alone (usually three months rent) will be more than double of that!
As far as I know (but do check the Munich Mietspiegel on this) suitable apartments cost at least €15/sqm monthly rent (excl. utilities, which will add another €200/month). Thus better budget €1500 to find a nice place quickly.
Some public schools have offer support courses for non-German-speaking kids, but yours will lose a school year by attending those.

what is the best solution not to waste 1 year. My daughter will turn to 6 by Feb,2016.

Oh, you didn't say that your daughter is still a pre-schooler.
In Germany, kids enter the school year starting in Aug./Sep. after their 6th birthday, so you still have half a year for her to get up to speed in German language - kids learn pretty fast, especially if you maximize her exposure. A German playgroup would probably be a good idea, and maybe you can start speaking German at home?
The only alternative is an international (foreign language) school, which has a price.

I am expecting my kids to teach me German . However my company offering me a 6 month German course.

International schools are not option for me since fees are really high and i cant afford it.