Can someone explain simply what the notation /64, etc mean?

Thanks for that illustration of our US deficit!  HA!  JK!

Yes, thank you very much for the help.  ; )

Hello timd1971 and welcome,

/64 is primarily an IPV6 notation for a quanity of subnet addresses. This link provides a really nice explanation and overall address sizing structure for you.

Hope this helps you out.

since there are SOOOO many addresses.... why the concern with the notation?  What's the purpose of why people specify this notation?  Do they really need that many addresses at their disposal?  I guess I just undersatnd why I see posts of people specify say like /24...  that's a lot of adddresses???  /64 even is a ton.

But yes, I do understand, that these addresses aren't merely just for client workstations etc, but also devices such as home appliances etc like thermostats, refrigerators etc etc etc.  And apparently other items also.  So I can definilty understand not wanting to have a shortage like what happened with IPv4. (or was it a memory limit of 640KB back in the DOS days?) ha!

This notation has been around for some time wrt IPV4 as this link provide some additional detail with the subnet mask reference, as well. IPV4 uses a 32 bit address versus IPV6 uses a 128 bit address and 2^128 provide a boot load more addresses that 2^32, so this is really why the notation is becoming a bigger deal as we migrate into IPV6. 

Comcast has not yet come out with their IPV6 static IP address structures and associated charges for same. However, I can assure you that it will be different than the IPV4 /30 = 1  routable static IP = $19.95, /29 = 5 routable static IPs = $24.95, /28 = 13 routable static IPs = $39.95, and does offer higher quantities for MetroEthernet advanced products . 

That is funny that you bring up the 640K elder computer memory limits because my first transportable Compaq computer in 1982 only had 64K with 256K floppy disk drive. Now that is really a gas as to the evolution. It seems that technology continues to evolve but in smaller increments these days. But IPV6 is a big deal especially to both software and hardware manufacturers.

Masters Tmittelstaedt and train_wreck;

I can't tell you how much your information helps me but yet SCREAMS at me saying "you really shouldn't be doing this Server Essentials thing".  You're really not high enough on the learning curve (me that is of course) to pull this off.  On the other hand, I'm amazed at your level of experience not to mention your thorough explanations; albeit over my head.  30 years ago, I'd have been all over this and probably spent some sleepless nights trying to understand, study, and learn this stuff.  You both also have compassion and understanding.  I personally know at least 15 IT people and their combined knowlege couldn't equal what you two have forgotten.   

Through 2014 my anualized IT expenses were approximately 40 - 50K with a maximum of 30 users.  That cost did not include any workstation computers (they're all HP by the way) and the beginning of the end of what was once a successful 29 year old business.  I'm holding on to what I can, and am taking this one day at a time and I'm a fighter!  However, you lose your client data files for 16 days while working in an environmental and occupational safety and health consulting firm and you are in BIG trouble.  Yesterday marked my first day in court regarding contract issues since my company missed federal reporting deadlines for these hard earned clients whom we didn't have files for.  Yes, I've been doing this long enough that 80% of our clients have 10 - 20 plus year relationships with us and they know this is not typical of our actions.  We also have a very good relationship with both federal and state agency representatives.  But at the end of the day, the potential fines for these clients can be up to 25K per day per violation.  I'd see me in court too!   Consider it similar to not filing your taxes, and ignoring the IRS letters for a few years.  But hey, Microsoft, Citrix and a few others will be the judge for them and their future and they're not looking to kindly upon the situation.

Anyway, enough of my rambling and really guy's here's what my cowrokers and I need or would like;

1.  A Server, NAS, or way to share files accross a network.  Currently, 70% of our files are located on Egnyte's Cloud Server.  The "webdav" Map Drive feature is working although all workstations are running the sync in real time.  Plus, the staff I have reduced to are not the most computer savy group.  So a file on the Cloud Server may end up on their local drives.  It'll sync most likely but it can be put in strange places.  It's also a pain to have to have a 500 gig hard drive and worry about running out of room.  Once I get a server up and running, I'll clean the 29 years of data up.  We generate a lot of little files but really no files that are large.

2.  Remote Access is critical.  We all have laptops that go to client sites with us.  Our field notes, reports, calculations, etc... have to be available.  That's why Citrix was selected for us.  Also, the DOD approves it for military defense contractors.  I'm not privy to our "classified" computer setups and don't need to be.  Defense cuts have us down to 3 desktops anyway so no big deal.

3. Shared combination scanners and printers (a couple Savin and one Panasonic).  When I received the new modem, Port 25 is blocked.  So, that's on my short list of things to fix.  Port 587 doesn't seem to get along with our Savin's or the Panasonic.

4. Backup to the cloud of course, and the feature that really got me excited about Essentials was having the ability to backup local machines.  Our staff is overworked and overstressed now and I don't see that changing in the near future.  They will make mistakes (file saving etc...).  These folks are fantastic, and we're currently at 5 total.  They go back with me to the Novell days.  I'd have to say they liked Netware much better than Citrix.  Over the last 5 years we'd average 80% uptime maximum,  

5.  Yep, I'm the guy with the two brand new HP ML350's (gen 5) with dual and redundant "everythings",  8 drives per machine, SAS 146 gig.  Dual 2.00 Ghz Xeon processors and 16 gig of RAM.  I've found the drivers' and it's behaving pretty nicely with Essentials.  The current version of FREENAS doesn't like it at all but NAS4FREE likes it just fine.

6.  Sitting next to me now is a Secure Computing SnapGear SG 565 Network, Gateway, Security device that I took offline when the 3939B modem arrived.  It could have been the way it was configured but for some reason, when it is being used, some of our computer workstations would only transmit at 100 megabyte.  Not that we're getting anything near that, but I think the server and the workstations would appreciate it.  it is a 10/100 model.  It was plugged into the Comcast SMC Modem with the modem in Bridge Mode taking care of the DHCP, and other functions.  However, when the servers were moved out of our offices in 2007, it provided the DHCP for the workstations only.  We had Citrix anyway.  It's never been run with a server at our location.

7.  I have one static IP address that I've had for years.  It goes back to when we had our own Exchange Server.  We used stacks of ISDN modems prior to Comcast being available.  Once we got on board with Comcast, and took on the Exchange Server, the dynamic IP worked for about a week (lol).  Probably don't need it anymore but it's here.

8.  Microsoft has the builk of everything with the Office 365 Business and the Exchange email being in their court.  I own a couple of domains that I've had forever so they're working fine with Office 365 Exchange.  I've read yoru posts a few times and now it makes sense why I always saw goises.local as our domain suffix.

9.  At this point, I don't care about IP anything (lol).  Seriously, IPV6 isn't important to me and the Server is eligible to have Essentials installed again, if it needs to be done.  I'm pretty good at it now since I've done it 10 times at least.  I'll let it autodetect an IP, assign it wherever you want.  Domain controller, toilet flusher, whatever you recommend, I'll do my darndest.  

My skill set is not anwhere near that of the hard working equally disgusted gentleman you've been helping.  He's probably much younger than I and has much more courage.  I understand in cocept from reading and video's that are available some of this technology, but I'm completely "out to lunch" with Network Addressing!  Can't get my head around it.  Bits of it (no pun intended) and the math of course are not a problem.  Inside, outside, geing on top of, sliding through, the local LAN and WAN is hard to grasp for some reason.  Yep, made a few of those routes up in my head but they probably exist.  But I'm still the person when they say set the IP to Static e.g. 10.1.10.2 and now the workstations can't see the internet - I freak out.  I've no experience with port forwarding, VPN's, etc...  I'll try to comprehend anything you tell me and I'll be the first to say "uncle" if I don't get it.

You all are a breath of fresh air and I appreciate that.  I'm ready to bring out my trusty 286 clone, with the Seagate 4096 megabyte drive connected to the Perstor Controller which would shove that drive to 115 to 125 megabyte!  Maybe I'll get agressive and do a Lantastic setup.  There was that network system I sold back in the late 1980's.  Two PC XT's on a bus card!!!!  Special cable that hooked up to their amber monitors and keyboards!  I just have to remember to set the file attributes correctly for the sharing.  Anybody up for Debug g=????

Best,

TG

Well see, I don't even knwo how to move the message.  I could delete it really.  I don't want to cloud up your issues at all.  Just let me know.

Yesterday really taught me a lot.  If I want to go down, I can handle that just fine.  I'd be glad to pay for IT.  Who wants the gig?  It's going to have to be remotely, though.  3 Million to 750K annual doesn't leave me much to pay anybody.  The server also stays in my building.

Seriusly, I've never been a forum poster so I'll delete the post or move it if you'd just tell me how (and I'm trying to setup a server).

TG 

It doesn't bother me.  But it might be best for the MODERATOR to move it into your own thread for organization...  mainly as this question was about IPv6 subnetting etc.

I don't know how to move it either.  Don't delete it, a MOD will move it.

I think you meant to post this in another section?  Might want to make it a new one all it's own?

You have a pretty tall list!  ; )

Seriously though, you've got a LOT going on there and the type of business your in etc...sounds like LOTS of liability etc?!

I know you don't want to hear this, but seriously, sounds like you should delegate all this to a IT pro.  If your anything like me, you're taking or have taken way too much on.  No matter how much you enjoy having that control of your system, it really sounds like it's time you handed it over to someone that does this day in and day out and in their sleep (i.e. someone like train_wreck and Tmittelstaedt if ya could!)  ; )

I am very small, 5 users or so..no liabilty etc.  Not much worry here...so I am going to keep at it as like you have been into tech all my life...but the server stuff is NEW territory as I never had a need for it...but I do now!  And yes, I am in my 40's, but that shouldn't matter.  As much as you have rattled off, I do get the impression you do know what you are talking about...your just a little lost on some of this NEW server territory like me...such as why we are here "looking" for help from people MUCH MORE experienced than us.  So yes, we do enjoy learning, even if it's taking time away...but I this part of my goal and just one of the many things on my list that must be set into play....just like what you have going on, but in a differnt way.

PS,

They don't mean what you think here at all about the Essentials deal, but I can understand your frustration:

"You're really not high enough on the learning curve (me that is of course) to pull this off."

I know for fact over at ServerFault you would get that response though.  II may have to back out of that and just user SuperUser : /

The table is incorrect in one respect. /64 is too small for a residence, unless it has just a single machine. In order to prevent identity tracking by IP address, all computers (or phones, tablets, DVR, TV, etc.) assume that they have a /64 address space from which they can select an address at random. The address selected changes periodically, so that new subsequent requests - such as web page requests - cannot be matched to the same machine. More commonly you would assign a /56 to the router, which would hand out /64s to each computer in your network. A /56 would allow 256 devices in your home.

This also prevents port scanning attacks, which work because there are many machines in a small search space. With IPv6, each individual machine exists by itself at some random address in a search space the same size as then entire IPv4 internet. Finding your computer to port scan it is like trying to find a single cork floating in the ocean.