TECHNICAL SUPPORT
Information: Why Suddenlink Blocks Port 25
► Summary:
The following information describes why Suddenlink High Speed Internet blocks port 25.
► Content
No one likes unsolicited e-mail (spam), except the spammers. Suddenlink continues to look for
opportunities to reduce the amount of spam going to its customers and leaving its network. Spam
typically comes in two primary forms either from computer virus programs that act as mail sending
programs, or from computers turned into mail servers specifically to send spam. To reduce unsolicited
bulk e-mail sent on our Suddenlink High Speed Internet network, we have instituted outbound SMTP
traffic blocking. Currently, we also block all inbound SMTP traffic in an effort to protect unsecured
computers from being used as a mail relay by potential spammers.
This security measure is designed to protect Internet users and the Suddenlink High Speed Internet
network and the vast majority of customers will not be affected by this practice in any way. The small
numbers of customers who use e-mail addresses outside of the @Suddenlink.net domain and do not
currently have their SMTP servers set for Suddenlink mail servers will need to change their settings.
We have provided answers to some of the most anticipated questions below
Q: What changes are actually being made?
A: Suddenlink will block all network traffic from residential customer IP addresses going outbound on
port 25 (SMTP) at our routers, unless it is being sent to a Suddenlink HSI SMTP server.
Q: Does this mean that I have to use my @Suddenlink.net e-mail address for everything I send?
A: No. You can use any valid e-mail address, but the email sent from your Suddenlink High Speed
Internet connection must be routed through a Suddenlink SMTP server.
Q. What are the correct SMTP server settings to use on the Suddenlink High Speed Internet
service?
A. Please contact one of our Customer Service Representatives at 1-800-490-9604 to receive the server
information for your area.
Q. Why is Suddenlink doing this?
A. The filter will drastically reduce the number of spam and virus emails originating from our
customers. Most Internet Service Providers have adopted this practice to reduce spam. We must take
this action to ensure that a few bulk e-mailers do not get the entire Suddenlink.net domain blacklisted
from sending mail to other Internet Service Providers.
Q. How will the filter help?
A. Typically, when a customer sends an email, it is routed to a Suddenlink.net mail server and the
Suddenlink server relays it to the recipient's server. Spammers and modern mass mailer viruses
commonly bypass the Suddenlink.net mail servers to send mail directly from their computer to others'
mail servers without routing it through a Suddenlink.net mail server. This filter will prevent spammers
from bypassing Suddenlink.net mail servers and delivering spam directly to Internet users. Also, this
filter prevents viruses such as W32.Klez.H@mm from propagating at all.
Q. Will this hinder my ability to send email?
A. This will not impact the vast majority of customers, but there may be some people using third party
mail servers. Any software configured to use an SMTP server other than smtp.*.Suddenlink.net to
deliver email directly to a recipient's server will no longer work. An indication of this problem may be
a message similar to this in your mail client:
A time-out occurred while communicating with the server. Account: `otheraccount.otherisp.com',
Server: `othersmtp.otherisp.com', Protocol: SMTP, Port 25, Secure(SSL): No, Error Number:
0x800CCC19
Customers using third party email services must configure their email clients to use
smtp.*.Suddenlink.net to send outbound email. Please remember that operating an e-mail or other
server on a residential Suddenlink High Speed Internet connection is a violation of our Acceptable Use
Policy.
Q. Will this affect web-based email services?
A. No. You can continue to use Suddenlink High Speed Internet WebMail, or services like HotMail and
Yahoo mail as you currently do.
Q. Will this affect inbound email at all?
A. No. This will not affect retrieval of inbound email from any service.
Q: Does this mean that Suddenlink reads my mail?
A: No. This measure merely affects how traffic is routed and does not in any way relate to the
substance of e-mail messages. We respect your privacy and do not read any email messages, instant
messages, online chats, or the content of other online communications that reside on or pass through
our Service.
Q: I am getting spam even though I have never given out my address. Is Suddenlink selling my
information?
A: We do not sell our customers' e-mail addresses. Sometimes spammers will try lists of common names
or words in different combinations to locate an active e-mail address. For more information, please
review our Privacy Policy.
Q: I am still receiving spam. How do I stop it?
A: This is just one step in efforts to reduce spam across the Internet. Please review our article on
Unsolicited Commercial E-mail for more information.
Q: I pay for my own domain name so I can send personal e-mail through that server. Why are you
blocking this legitimate use?
A: We understand that some customers have vanity domain names and this action should not keep you
from using your personal domain name. To ensure your ability to send email from your personal
domain, your mail client must be set to a Suddenlink outgoing mail server. This change in settings will
be transparent to email recipients, and will not impact your ability to receive email. If you have a
business requirement to bypass the Suddenlink mail servers, please contact Suddenlink Business
Services for additional options.
Q: Why didn't Suddenlink notify customers in that it would begin blocking all network traffic from
residential customer IP addresses going outbound on port 25 (SMTP) at Suddenlink's routers (unless
it is being sent to a Suddenlink HSI SMTP server)?
A: Port 25 is on Suddenlink's blocked list as noted in the Subscriber Agreement and in information
found on our support site. This information is available to customers at all times, and customers are
instructed to routinely check the Policy for information on acceptable uses of the service and network.
The current blocking of Port 25 does not reflect a change in our policy, but rather an enforcement of
said policy for the benefit of all Suddenlink High Speed Internet customers. This effort is mean to
reduce unsolicited bulk e-mail sent on our Suddenlink High Speed Internet network.
Q: Why was Port 25 not blocked to universities previously?
A: Suddenlink understands that a large percentage of customers are students. At the time the initial
blocks were implemented, school was in session and we created an exemption. This allows us to work
with the colleges in more detail before we impact their students, and we chose the summer months
since most of the schools are not in major sessions at this time.
Q: What are Suddenlink customers who send mail via Port 25 supposed to do?
A: Customers must configure their email clients to use smtp.*.Suddenlink.net to send outbound email.
Please remember that operating an e-mail or other server on a residential Suddenlink High Speed
Internet connection is a violation of our Acceptable Use Policy.
► Applies To
·
We are blocking port 25.
·
Online safety, protecting your computer and our network.
·
More about spyware,adware,trojan horses,parasites and other viruses.
·
More about how to protect yourself against viruses.
