![[LISTSERV - the mailing list management classic]](/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 786183 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 351712 LISTSERV.LIV.AC.UK (Linux 2.6.32) 3 324593 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 275603 LISTS.PSU.EDU (AIX 6.1) 5 230687 LISTES.ULAVAL.CA (Linux 3.10.0) 6 215396 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 7 214544 LISTSERV.UGA.EDU (Linux 2.6.32) 8 191377 LISTS.HAWAII.EDU (Linux 2.6.32-754.35.1.el6.x86_64) 9 190646 LISTS.UFL.EDU (Linux 2.6.32) 10 178510 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 11 171411 LISTSERV.TDBANK.CA (Windows Server 2012 R2 Datacenter x64 Edition) 12 167220 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 149560 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 14 144995 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 15 141881 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 16 138487 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 125798 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 18 121288 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 121152 MASSMAIL.VCU.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 20 119268 LISTSERV.UTORONTO.CA (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 5188324 LISTES.ULAVAL.CA (Linux 3.10.0) 2 4992881 LISTS.PSU.EDU (AIX 6.1) 3 2288966 LS.KULEUVEN.BE (Linux 2.6.32) 4 1591585 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1442398 LISTSERV.UGA.EDU (Linux 2.6.32) 6 1325170 LISTS.WAYNE.EDU (Linux 2.6.32) 7 1217494 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1193905 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1146397 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 1127961 LIST.MSU.EDU (Linux 3.10.0) 11 1059036 LISTS.UFL.EDU (Linux 2.6.32) 12 960501 LISTS.UMN.EDU (Linux 3.10.0) 13 937033 LISTSERV.UA.EDU (Linux 4.12.14) 14 926838 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 852136 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 829744 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 827828 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 813625 LISTSERV.UH.EDU (Linux 3.10.0) 19 809232 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 20 749922 LISTS.MAINE.EDU (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 34750 LISTES.ULAVAL.CA (Linux 3.10.0) 2 17009 LISTS.PSU.EDU (AIX 6.1) 3 11852 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 5 9599 LISTS.UFL.EDU (Linux 2.6.32) 6 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 7 7523 LISTSERV.LIV.AC.UK (Linux 2.6.32) 8 6734 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 5789 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 5482 LISTSERV.UTORONTO.CA (Linux 3.10.0) 11 5289 LS.KULEUVEN.BE (Linux 2.6.32) 12 5023 LISTSERV.TAMU.EDU (Linux 3.0.101) 13 4913 LISTS.UMN.EDU (Linux 3.10.0) 14 4887 LISTSERV.UGA.EDU (Linux 2.6.32) 15 4235 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4179 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3984 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3723 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 19 3334 LIST.UVM.EDU (Linux 2.6.32) 20 3319 LISTSERV.BROWN.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 756962 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 341515 LISTSERV.LIV.AC.UK (Linux 2.6.32) 3 323926 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 272547 LISTS.PSU.EDU (AIX 6.1) 5 230467 LISTES.ULAVAL.CA (Linux 3.10.0) 6 209921 LISTSERV.UGA.EDU (Linux 2.6.32) 7 189481 LISTS.UFL.EDU (Linux 2.6.32) 8 189187 LISTS.HAWAII.EDU (Linux 2.6.32-754.35.1.el6.x86_64) 9 176326 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 10 144756 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 11 141341 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 12 140089 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 13 138293 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 124041 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 15 117917 LISTSERV.UTORONTO.CA (Linux 3.10.0) 16 117778 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 17 117335 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 112269 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 19 111366 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 110375 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 59276 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 2 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 3 43187 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 41807 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 5 36015 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 6 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 7 33581 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 8 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 9 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 10 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 11 28304 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 12 27708 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 13 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 14 27390 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 15 27206 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 16 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25576 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24316 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 23332 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0)