Optimize Optimum Online (OOL)

Hopefully the following steps will assist you in optimizing your OOL speed. OOL is Optimum Online, a cable modem service provided by Cablevision in the NY?NJ/CT Metro area. Though I refer to OOL below, the following steps are general enough to apply to most cable modem users. If you have questions, the best thing to do is post them in the OOL forum on DSLReports where there are many folks who have mastered the art of OOL optimization. It's also where the basis for everything on this page has come from.

The assumption in the below steps is that you already have OOL cable modem service and a modem and that the modem is plugged in and you are able to access the internet. If not, then there's no reason to start optimizing your connection and the below steps won't help you (at least yet). You can availability information at the OptimumOnline home page. If you're having a problem getting connected at any speed, contact OOL directly via phone, OOL Live Online Support or post your problem in the OOL forum on DSLReports.

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Lets walk through the steps you should go through. There's not necessarily a specific order, but if you're having a problem, it's probably best to start at the beginning. 

Step 1 - The cable to the modem
An important step is to make sure, if at all possible, that the cable running to the cable modem is off the first split once it enters the home. Most folks have a splitter that allows multiple sets to get cable. In my case, the first splitter is in my basement and it split the incoming cable from outside to drops for upstairs and downstairs. I added a new two-way splitter and had the cable to the modem run off the new splitter and the other half of the new splitter run to the other existing splitter. This should cost about $5 for the splitter and small piece of cable to connect to the existing splitter if one already existed.

Step 2 - Optimize your settings
The next thing to do would be to download a program called DrTCP. This is a Windows 9x/Me/NT/2000/XP compatible program which allows you to tweak your network settings. This optimization needs to be run on each computer that will access OOL. Once downloaded (there's no install), run DrTCP and start by changing the following settings:
Set the TCP Receive Window to one of the following based on your speed tier:
64240 for 10mb or less; 128480 for 10-20mb; 256960 for over 20mb
Set the Path MTU Discovery to Yes
Select your network card in the drop-down list and then set the MTU to 1500
Click the Apply button and then the Exit button. 
You must reboot for these changes to take effect!!
After rebooting, re-run DrTCP on the machine, re-select your appropriate network card from the drop-down list and verify that all the settings were retained.

Here's a screenshot of my DrTCP settings.

If you have a Macintosh, look here for a program that allows you to tweak your settings using the above values.

Step 3 - Verify the optimization
At this point, you should run a Tweak Test on the DSLReports site to see if anything else is identified. When you go to the page, a Java applet should load and appear. There will a Start button that you should click to run the test. Once the test is completed, the Results button will become enabled so go ahead and click on it. A new page will be displayed asking for what service, speed and operating system you are running. 

Select the following:
Service: cable
Speed: 5000
Operating System: whatever is appropriate for the machine you're running the test on
Connection: normal
and then press the recommend button.

On the results page that is displayed, you want to verify in the left-most column that the Receive Window (RWIN) setting shows what you set above based on your speed tier and that Path MTU Discovery shows On. In the middle column you want to verify that the Max Packet Sent (MTU) and the Max Packet Recd (MTU) settings show 1500. If you are using a cable modem router, and DrTCP shows the MTU as set to 1500 but the Tweak Test shows a lower value, you might need to adjust the MTU on your router. See Step 5 below for information regarding routers.

There should not be any issues identified under the settings on the left-most column. You might see a message or two under the middle column which highlights some re-transmission errors or stalls. Within reason these are normal and not an indication you have any problems. You can ignore any issues identified in the 3rd column as they are not normally relevant to tweaking your connection. If anything else is highlighted or there are questions you have on the results, the page contains a URL that is displayed under the settings that should be highlighted and copy/pasted into a new posting on the DSLReports forum for someone to respond to.

Step 4 - Run speed tests
Before you do speed tests, you need to understand what's happening when they are run. You computer goes out through the cable modem and onto Optimum Online's network. From there it goes out onto the internet and through the internet to a server hosted by someone else on their network and then all the way back. All of this involves lots of opportunities for problems to be introduced that affect your speed. So you need to take these speed tests with a grain of salt. They are just a indication of what speeds you are receiving at the specific moment you run it. With that said, lets look at the 2 tests that can be run and the differences between them.

The first test I suggest is the OOL FTP test. This test removes the external (non OOL) internet from being involved as the server being accessed is on the same (hypothetical) network as you are on. What occurs when you click on the link is a 64MB file will start to download to your machine from a ftp server that OOL provides. Depending on your browser and the settings you have, you might be prompted to  Save or Open the file. It doesn't really matter which you do. What you'll then see is a window showing the transfer of the file that looks something like this. What's important here is the Transfer rate that is shown. If using IE, the initial rate will start very high and then come down after the first few updates to the window. Once you hit about 10-20% of transferring the file, the value shown should be accurate. The norm is to get between 400KB and 1MB during this transfer. If you don't achieve that transfer rate, wait a few minutes and try again. If the rate is still out of the norm , create a new posting on the DSLReports forum for someone to respond to and include the copy/paste url from running a Tweak Test on the DSLReports site from Step 3 above.

The second speed test is a test which will measure your download and upload speeds. Currently OOL doesn't host a version of this test though it's planned for the future so we need to run the test by accessing a server with the test that exists out on the "real" internet. That means all the factors that could effect performance mentioned at the beginning of this step come into play. The internet might have congestion which slows down the test for you, the network that is hosting the speed test server might have some congestion as well, and even the speed test server might be over-utilized and slow because of everyone accessing it. With that said, the server which seems to provide us OOL users with the best results is the NYC Speakeasy Speed Test , PHL Speakeasy Speed Test  and the BOS Speakeasy Speed Test. When you go to the test, a Java applet will run and be displayed. Click on the Start button in the applet to initiate the test. Once the test is completed,  a new page with be displayed that will show your results. 

Because of all the possibilities for outside factors to effect your performance, you could run this test 5 times in a row and get relatively significant differences in the results that are achieved. Run multiple tests at various times of the day over a couple days to see if there's some consistency in the results. 

Note: Any results above are those that reflect my "norm". They won't necessarily reflect yours and that doesn't mean there's anything wrong with your results. Depending on the modem you use (I happen to have a Terayon Terajet), where you are located among probably 20 other things, your norm or max speed is determined. Anything above 3500 down is acceptable. A suggestion would be to check out the DSLReports speed test archive where you can enter in your specific zip code and see what others in your general vicinity are achieving.

Step 5 - Optional further tweaking
What has been outlined so far in the above steps should get the majority of people the maximum performance possible with a minimum of effort. The rest of what you can do is more trial-and-error. In most cases the effort to find those extra few KB is large compared to any noticeable improvement, but for the hard-core tweaker the challenge is really the reason to continue on.

The recommendation regarding the TCP Receive Window (RWIN) setting is what has been proven to given the vast majority of OOL users the best performance. But it's probably the place where trial-and-error changes will provide you with slightly more speed. What you can try is to increase the TCP Receive Window (RWIN) value using DrTCP to see if any speed increases can be gained. Again, you'll need to make the change, apply the change and reboot for the change to take effect. This can be time consuming when you're constantly rebooting to get that "just right" value. As the TCP Receive Window is increased, you can introduce re-transmissions because of it.  If you are running Win95 or Win98 and you can't seem to get a value > 65536 to stick, you probably need the vtcp.386 update applied to your machine. Go here if you need the update for Win95 or go here if you need the update for Win98.

If you are using a cable modem router such as a Linksys or Netgear or any of the other vendors that manufacture these products, you need to make sure that the MTU setting on the router is also set for 1500. This should normally be the case but if the Tweak Test shows a value other then 1500 and DrTCP shows 1500, it might need to be changed in the router configuration. Depending on your router and it's capabilities, this should be possible. Check the documentation for your specific router or look in the appropriate Router DSLReports forum for guidance. If you have a Linksys, you want to make sure you're running firmware version 1.39 or later. Versions prior to that caused the router to be a bottleneck. You can check the version of your Linksys firmware by going to http://192.168.1.1/Status.htm .  Today's routers should not slow down your speeds substantially, though you could see a slight drop due to the additional overhead. A big exception to this rule is when you are using wireless networking. You can expect to see a 50% or more drop in performance when communicating wirelessly to your router/access point using 802.11b wireless. 802.11g and 802.11n should allow for full speed, up to 30mb. If you suspect the router, it is best to take it out of the picture and directly connect the computer to the cable modem to verify you are tweaked and then work through any router issues.

If you have a cable modem hooked up to your computer via USB instead of a physical network card (NIC), their seems to be a pretty significant performance drop that can occur. These days, you can get a ethernet network card (NIC) for as low as $10 after rebates and discounts at popular computer stores nationwide. If you do purchase an ethernet network card (NIC) for your computer, make sure to re-optimize all your settings as changes you've made can be lost in the upgrade.


Well I hope you got some performance improvement by following the above steps and it didn't take too much time or effort. If you have any question, the best place to ask them is in the OOL forum on DSLReports where some folks seem to be on 24 hours a day to answer your question or help diagnose your specific problem. My name on DSLReports is GeekNJ. Also, if there's something out of the ordinary that seems to be happening all of a sudden, someone might have posted something on the forum regarding an outage or performance issue. Seeing if others are effected doesn't make your problem go away, but at least it might identify why you're having an issue, and you might even see how many other folks are impacted and an ETA on getting it resolved.

Contact: david@levinecentral.com