![[LISTSERV - the mailing list management classic]](https://www.lsoft.com/images/HDR-LISTSERV-sm.gif)
There are many possible ways to measure the relative "importance" or "size" of LISTSERV sites: number of lists, number of subscribers, number of messages delivered, etc. In most cases, the number of messages delivered is used to rank mailing list managers, because it is the most accurate measurement of the amount of activity on the server. But, depending on what you are looking for, other variables may be more appropriate. There are currently three LISTSERV "Top 20" lists, ranking the various servers according to:
In addition, you can view a list of the Top 20 lists in the network (by number of subscribers).
The statistics are gathered daily by a monitor at L-Soft which polls all the LISTSERV sites that participate in the "open" LISTSERV network over the worldwide Internet. Corporate servers operating in a "closed" environment are not included.
The statistics are organized in monthly reports. The message volume figures are a flat average of the accumulated traffic for the entire month. Thus, a server that delivers 300,000 messages per month will show a daily average of 10,000 messages. In practice, there is a lot less traffic during the weekend, and even during business days there can be significant fluctuations (~30%). The list statistics (number of lists, number of subscribers, largest lists in the network) are measured as of the last day in the month.
For the current month, the message volume figures are averaged based on the number of days that have elapsed. In practice, the figures are not very meaningful in the first few days, especially if the month starts on a weekend. In that case it is best to refer to the previous month for more accurate figures.
A fourth "Top 20" list is available for the more technically oriented: Number of messages generated by the server. This corresponds to the number of mail messages created by the server while processing postings to its mailing lists. LISTSERV delivers its mail using an intelligent mail delivery function called DISTRIBUTE, which improves mail delivery times and reduces bandwidth usage by spreading the delivery chore over scores of participating servers. Each of these servers processes the recipients for its service area (typically its organization or campus). In most cases, DISTRIBUTE simply alters the manner in which the mail is delivered, and the number of messages forwarded to other sites for optimized delivery is roughly equal to the number of messages received by other sites for the same purpose. In some cases, however, this is not the case, either because the server elected to serve a much wider service area than its own organization, or because it is explicitly forwarding all its deliveries to another machine (for instance, many mainframe-based servers forward their mail to a workstation or PC for delivery).
Pos Recipients Site --- ---------- ---- 1 813335 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 654581 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 460576 LISTS.PSU.EDU (AIX 6.1) 4 350212 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 5 301884 LISTSERV.LIV.AC.UK (Linux 2.6.32) 6 252842 LISTES.ULAVAL.CA (Linux 3.10.0) 7 236949 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 8 228620 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 9 223885 LISTSERV.UGA.EDU (Linux 2.6.32) 10 213629 LIST.UNM.EDU (Linux 2.6.32-754.12.1.el6.x86_64) 11 211863 LISTS.HAWAII.EDU (Linux 2.6.32-754.23.1.el6.x86_64) 12 206006 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 13 203949 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 14 202719 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 15 201545 LISTS.UFL.EDU (Linux 2.6.32) 16 196517 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 17 182311 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 181084 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 19 179059 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 20 158771 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5050873 LISTS.PSU.EDU (AIX 6.1) 2 3874575 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2203224 LS.KULEUVEN.BE (Linux 2.6.32) 4 1421759 LISTSERV.UGA.EDU (Linux 2.6.32) 5 1353501 LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 1302942 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 1282581 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1270247 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 9 1234091 LISTS.WAYNE.EDU (Linux 2.6.32) 10 1059036 LISTS.UFL.EDU (Linux 2.6.32) 11 982099 LISTS.UMN.EDU (Linux 2.6.32) 12 944029 LIST.MSU.EDU (Linux 3.10.0) 13 847854 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 14 847809 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 842669 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 17 812928 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 798412 LISTSERV.UH.EDU (Linux 3.10.0) 19 779231 LISTSERV.UA.EDU (Linux 4.12.14) 20 737514 LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition)
Pos Lists Site --- ----- ---- 1 27563 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16686 LISTS.PSU.EDU (AIX 6.1) 3 11568 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 10216 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 5 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 6 9599 LISTS.UFL.EDU (Linux 2.6.32) 7 8333 MARIST (VM/SP 2.0) 8 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 9 7199 LISTSERV.LIV.AC.UK (Linux 2.6.32) 10 6700 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 11 6054 LISTSERV.UGA.EDU (Linux 2.6.32) 12 5467 LISTS.UMN.EDU (Linux 2.6.32) 13 5052 LISTSERV.TAMU.EDU (Linux 3.0.101) 14 4748 LS.KULEUVEN.BE (Linux 2.6.32) 15 4372 LISTSERV.UTORONTO.CA (Linux 3.10.0) 16 4190 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 4041 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 4026 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3998 LISTS.QUEENSU.CA (Linux 3.10.0) 20 3539 LISTSERV.BUFFALO.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 783873 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 653804 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 456180 LISTS.PSU.EDU (AIX 6.1) 4 349415 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 5 293477 LISTSERV.LIV.AC.UK (Linux 2.6.32) 6 252734 LISTES.ULAVAL.CA (Linux 3.10.0) 7 219238 LISTSERV.UGA.EDU (Linux 2.6.32) 8 213396 LIST.UNM.EDU (Linux 2.6.32-754.12.1.el6.x86_64) 9 210463 LISTS.HAWAII.EDU (Linux 2.6.32-754.23.1.el6.x86_64) 10 200144 LISTS.UFL.EDU (Linux 2.6.32) 11 199852 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 12 198952 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 13 197809 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 193632 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 15 180841 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 178899 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 17 178143 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 18 152678 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 19 147531 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 134017 LISTSERV.UA.EDU (Linux 4.12.14)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 55104 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 3 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 4 43384 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 5 41763 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 6 36535 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 8 33600 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 9 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 10 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 11 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 12 28311 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 13 27854 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 14 27709 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 15 27399 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 16 26419 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25008 2019-STEM-EVENT-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24765 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 20 24464 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)