Web Server Statistics

Preceding One-Year Period

Visits (Successful Accesses)

From 14 Feb 2025 0:04:08 to 13 Feb 2026 23:59:10

 A category is chosen using these tests applied in order:

 "Bot?",    Hit from the same host requested robots.txt. (As Web indexers do.)
 "LSU",     Host name matches Perl regular expression \.lsu\.edu$.
 "Outside", Any host name.

     All   Brwsrs  Brand     : Version Pct, ...
  60.13%   71.22%  Chrome    : 134.0.x  8.4%,  142.0.x  5.7%,  114.0x  5.2%, 
                             : 135.0.x  4.4%,  133.0.x  3.9%,  139.0.x  3.7%, 
                             : 140.0.x  3.6%,  120.0x  3.5%,  143.0.x  3.3%, 
                             : 131.0.x  3.2%,  132.0.x  3.0%.
                             : Android  8.2%,  Linux  3.5%,  Macintosh 28.9%, 
                             : Unknown  0.5%,  Windows 58.2%,  iPad   0.0%, 
                             : iPhone  0.7%,  iPod   0.0%.
  10.71%   12.68%  Safari    : 604.1x 41.4%,  605.1x 29.8%,  537.36x 22.0%, 
                             : 601.2.4 facebookexternalhit/1.1 Facebot Twitterbot/1.0  2.3%, 
                             : 10600.6.3  1.7%,  601.1x  0.5%,  184.1  0.3%, 
                             : 600.2.5  0.2%,  260.1  0.1%,  180.1  0.1%, 
                             : 172.1  0.1%.
                             : Android 22.6%,  Linux  0.1%,  Macintosh 33.1%, 
                             : Unknown  0.8%,  Windows  0.5%,  iPad   2.0%, 
                             : iPhone 40.8%,  iPod   0.1%.
   7.51%    8.90%  Firefox   : 133.0 14.1%,  111.0 10.7%,  142.0x  9.0%, 
                             : 144.0  4.5%,  131.0  4.0%,  136.0  4.0%, 
                             : 140.0  3.9%,  145.0  3.9%,  137.0x  3.5%, 
                             : 143.0  3.4%,  146.0  2.6%.
                             : Android  2.2%,  Linux 25.4%,  Macintosh 19.4%, 
                             : SunOS  0.0%,  Unknown  0.2%,  Windows 52.8%.
   7.40%           ChatGPT-User
   5.80%    6.87%  Netscape  : 5.0x  100.0%,  5.2    0.0%,  4.0    0.0%, 
                             : 4.05   0.0%,  2.02E  0.0%,  4.77   0.0%.
                             : Android  0.0%,  Unknown 99.0%,  Windows  1.0%.
   1.40%           Baiduspider/2.0
   1.06%           Python    : 3.12 aiohttp/3.x 93.9%,  3.10 aiohttp/3.x  3.1%, 
                             : 3.11 aiohttp/3.x  1.6%, 
                             : 3.14 aiohttp/3.13.3  0.7%, 
                             : 3.13 aiohttp/3.1x  0.7%.
                             : Unknown 100.0%.
   0.67%           python-requests: 2.32.x 64.0%,  2.27.1 21.0%,  2.31.0 14.5%, 
                             : 2.26.0  0.2%,  2.28.x  0.1%,  2.25.1  0.1%, 
                             : 2.22.0  0.0%,  2.29.0  0.0%,  2.11.1  0.0%.
                             : Unknown 100.0%.
   0.48%           curl      : 8.4.0 94.2%,  8.10.x  5.6%,  8.5.0  0.1%, 
                             : 7.76.1  0.1%,  7.30.0  0.0%,  8.11.1  0.0%, 
                             : 8.13.0  0.0%,  8.1.2  0.0%,  7.88.1  0.0%, 
                             : 7.81.0  0.0%.
                             : Unknown 100.0%.
   0.43%           AppleWebKit: 605.1.15x 69.9%,  537.36x 28.8%, 
                             : 606.2.3x  0.6%,  528.16 (KHTML, like Gecko)  0.1%, 
                             : 531.22.x  0.1%,  533.20.25  0.1%, 
                             : 528.8 (KHTML, like Gecko)  0.1%, 
                             : 537.73 (KHTML, like Gecko)  0.1%, 
                             : 312.1 (KHTML, like Gecko)  0.1%, 
                             : 534  (KHTML, like Gecko) MsnBot-Media /1.0b  0.0%, 
                             : 601.1.46 (KHTML, like Gecko) Mobile/21B91 Quark/7.1.1.2184 Mobile  0.0%.
                             : Linux  2.5%,  Macintosh 28.5%,  SymbianOS  0.0%, 
                             : Unknown  0.1%,  Windows 25.8%,  iPad   2.7%, 
                             : iPhone 40.3%.

Notes: MSIE refers to Microsoft Internet Explorer, Netscape refers to Netscape Navigator, SeaMonkey refers to SeaMonkey and to older versions (called the Mozilla Suite). Firefox refers to Mozilla Firefox and to older versions (Mozilla Firebird, Firebird™ and Phoenix). All shows the percentage of accesses using the corresponding user agent, Brwsrs only counts recognized web browsers. A version ending in x refers to multiple sub-versions.

 Visits  Crawler
 657139  45.134.225.250
 541715  185.196.220.113
 454373  193.142.147.5
 221981  Googlebot
  88416  196.251.90.217
  84181  196.251.70.180
  68497  bingbot

    Visits  Hosts  Originating Domain
     48547   6157  hwclouds-dns.com
     36639  12774  amazonaws.com
     33592     90  20.171.207
     19423   6369  googleusercontent.com
     16575   2805  sbcglobal.net
     15318   1983  cox.net
     13590   1098  googlezip.net
     13146    394  baidu.com
     10769   2590  wlan.lsu.edu
      6936     27  207.166.160
      6906      1  mikegpts-XXX.lsu.edu
      6732     61  ece.lsu.edu
      6686     36  74.7.227
      6583   3667  spectrum.com
      6445   3573  comcast.net

    Visits  Hosts  Originating Country or Group
    454047  171602  Unknown Origin
    170222  47681  com   - Commercial
     82338  23898  net   - Network Provider
     29892   4170  edu   - Educational
      8621   8048  br    - Brazil
      6489   1948  de    - Germany
      2751    345  pl    - Poland
      2595   1027  cn    - People's Republic of China
      2170   1431  in    - India
      1741    989  fr    - France
      1595    906  ru    - Russia
      1246    903  ca    - Canada
      1109    135  us    - United States
       954    887  ar    - Argentina
       949    286  org   - Non-commercial, non-governmental organization

Visits Via Search Engine
  1430 www.google.com
    59 scholar.google.com
    24 www.semanticscholar.org
    18 www.bing.com
    13 google.com
     7 yandex.ru
     4 www.math.lsu.edu
     3 ya.ru
     2 cn.bing.com
     2 yandex.com

 #e #s #p Visits Using Search Strings...                ...Found Page (Most Visits)
  1  1 401   483  ece /robots.txt
  1  1  1   201  https://www.ece.lsu.edu/kak/GarbhaUpanishad.pdf/kak/GarbhaUpanishad.pdf
  1  1  7   118  www.ece.lsu.edu /kak/Busan.html
  1  1  1    72  https://www.ece.lsu.edu/kak/MahabharataII.pdf/kak/MahabharataII.pdf
  1  1  1    23  https://www.ece.lsu.edu/kak/a3.pdf /kak/a3.pdf
  1  1  1    21  garbh upanishaf /kak/GarbhaUpanishad.pdf
  1  1  1    20  https://www.ece.lsu.edu/kak/ast.pdf /kak/ast.pdf
  1  1  1    19  https://www.ece.lsu.edu/news/2011/Frank-Walk-Room-map.pdf/news/2011/Frank-Walk-Room-map.pdf
  1  1  1    17  https://www.ece.lsu.edu/koppel/ /koppel
  3 12 12    15  的 /gunturk/EE7730/L9.ppt
  1  1  1    12  https://www.ece.lsu.edu/v/ /v
  1  1  1    10  https://www.ece.lsu.edu/kak/taj.pdf /kak/taj.pdf
  1  1  1     9  https://www.ece.lsu.edu/kak/zoro.pdf /kak/zoro.pdf
  1  1  1     8  https://www.ece.lsu.edu/kak/kakosu.html /kak/kakosu.html
  1  1  1     7  https://www.ece.lsu.edu/ee4720/ /4720
  1  1  1     7  https://www.ece.lsu.edu/kak/shruti.pdf /kak/shruti.pdf
  1  1  1     7  https://www.ece.lsu.edu/kak/Time2.pdf /kak/Time2.pdf
  3  3  1     7  medical image segmentation /gunturk/Topics/Segmentation-1.pdf
  1  1  1     7  Tiling+of+Iteration+Spaces+for+Multicomputers./jxr/papers/conf/icpp90.PS
  1  1  1     6  https://www.ece.lsu.edu/ee3755/2013f/cla.pdf/ee3755/2013f/cla.pdf

#e: Number of different search engines used, link is to the most common engine.
#s: Number of search strings the line actually reports on. For example, if the #s entry were 5 and the string shown were "Computers" the line might report on search strings "Computers", "Computer", "+Computers", "COMPUTERS", and even "-computers".
#p: Number of distinct pages that were visited, the one with the most visits from the string is shown.

Refused (Unauthorized)

From 15 Feb 2025 13:42:43 to 13 Feb 2026 23:02:30

 A category is chosen using these tests applied in order:

 "Bot?",    Hit from the same host requested robots.txt. (As Web indexers do.)
 "LSU",     Host name matches Perl regular expression \.lsu\.edu$.
 "Outside", Any host name.

     All   Brwsrs  Brand     : Version Pct, ...
  72.85%   73.89%  Chrome    : 135.0.0.0 20.1%,  134.0.0.0 18.4%, 
                             : 132.0.x  5.3%,  127.0.x  4.7%,  107.0.0.0  4.5%, 
                             : 120.0.x  4.4%,  113.0.x  3.9%,  131.0.x  3.7%, 
                             : 114.0.x  2.9%,  122.0.x  2.9%,  100.0.x  2.5%.
                             : Android  5.8%,  Linux  5.3%,  Macintosh 41.2%, 
                             : Unknown  0.1%,  Windows 46.1%,  iPhone  1.5%.
   9.94%   10.09%  Safari    : 605.1.1x 40.4%,  537.36 30.9%,  604.1x 20.5%, 
                             : 260.1  1.1%,  600.2.5  0.9%,  184.1  0.9%, 
                             : 170.1  0.7%,  533.0  0.4%,  532.0  0.2%, 
                             : 419.3  0.2%,  6531.39.1  0.2%.
                             : Android 30.9%,  Linux  0.5%,  Macintosh 43.9%, 
                             : Windows  0.7%,  iPad   2.1%,  iPhone 21.3%, 
                             : iPod   0.5%.
   8.58%    8.70%  Firefox   : 133.0 73.2%,  123.0x  4.9%,  131.0  3.3%, 
                             : 145.0  1.4%,  128.0  1.4%,  136.0  1.2%, 
                             : 135.0  1.0%,  147.0  0.8%,  3.6    0.6%, 
                             : 3.6.4  0.6%,  9.0x   0.6%.
                             : Android  0.2%,  Linux  8.4%,  Macintosh 77.3%, 
                             : Unknown  0.6%,  Windows 13.5%.
   6.68%    6.78%  Netscape/5.0 AppleWebKit/537.36
   0.86%           Baiduspider/2.0
   0.26%    0.27%  MSIE      : 9.0   33.3%,  5.0   20.0%,  8.0   13.3%, 
                             : 7.0   13.3%,  6.0   13.3%,  10.0   6.7%.
                             : Windows 100.0%.
   0.25%    0.25%  Opera     : 9.80   7.1%,  9.44.  7.1%,  9.53.  7.1%, 
                             : 8.49.  7.1%,  8.12.  7.1%,  9.89.  7.1%, 
                             : 9.56.  7.1%,  9.10.  7.1%,  8.79.  7.1%, 
                             : 9.85.  7.1%,  8.68.  7.1%.
                             : Linux 50.0%,  Windows 50.0%.
   0.19%           Wget      : 1.21.3 63.6%,  1.25.0 36.4%.
                             : Unknown 100.0%.
   0.18%           Sogou web spider/4.0
   0.11%           python-requests/2.31.0

Notes: MSIE refers to Microsoft Internet Explorer, Netscape refers to Netscape Navigator, SeaMonkey refers to SeaMonkey and to older versions (called the Mozilla Suite). Firefox refers to Mozilla Firefox and to older versions (Mozilla Firebird, Firebird™ and Phoenix). All shows the percentage of accesses using the corresponding user agent, Brwsrs only counts recognized web browsers. A version ending in x refers to multiple sub-versions.

     Denys  Hosts  Originating Domain
       324     27  207.166.160
       311     30  20.171.207
       221    151  143.14.6
       220    213  amazonaws.com
       150    141  googleusercontent.com
       133    133  acedatacenter.com
        57      2  74.7.227
        46     44  sogou.com
        44     12  168.62.29
        39     34  baidu.com

     Denys  Hosts  Originating Country or Group
      4391   3393  Unknown Origin
       755    721  com   - Commercial
       167    154  net   - Network Provider
       101    101  br    - Brazil
        58     14  de    - Germany
        23     17  in    - India
        22      4  pl    - Poland
        22     22  ar    - Argentina
        13     13  ca    - Canada
        10      7  jp    - Japan

 Lnks   Denys  ...From Links on Host      Most Common Linking Page and Target
  100     680  www.ece.lsu.edu             182 From → /v/s/genus_comref.pdf

 #e #s #p  Denys Using Search Strings...                ...Found Page (Most Denys)
  1  1  1     1  ece /jxr/courses/7700-dsparch/stuff

#e: Number of different search engines used, link is to the most common engine.
#s: Number of search strings the line actually reports on. For example, if the #s entry were 5 and the string shown were "Computers" the line might report on search strings "Computers", "Computer", "+Computers", "COMPUTERS", and even "-computers".
#p: Number of distinct pages that were refused, the one with the most denys from the string is shown.

Status Codes (Access Outcomes)
  Count Code Description
  10255 401  Unauthorized.

Misses (Target Missing, etc)

From 14 Feb 2025 0:17:56 to 13 Feb 2026 23:59:48

 A category is chosen using these tests applied in order:

 "Bot?",    Hit from the same host requested robots.txt. (As Web indexers do.)
 "LSU",     Host name matches Perl regular expression \.lsu\.edu$.
 "Outside", Any host name.

     All   Brwsrs  Brand     : Version Pct, ...
  70.90%   87.50%  Chrome    : 60.0.x 41.7%,  59.0.x 10.1%,  61.0.x  8.8%, 
                             : 126.0.x  3.6%,  85.0.x  2.7%,  90.0.x  2.1%, 
                             : 91.0.44x  1.6%,  122.0.x  1.6%,  135.0.x  1.5%, 
                             : 114.0.x  1.5%,  120.0.x  1.3%.
                             : Android 39.4%,  Linux  2.2%,  Macintosh 24.6%, 
                             : Unknown  0.1%,  Windows 33.0%,  iPad   0.0%, 
                             : iPhone  0.7%.
   4.86%           UT-Dorkbot: 1.2   99.1%,  1.2\   0.4%, 
                             : 1.2;waitfor delay '0:0:4'--  0.1%, 
                             : 1.2';waitfor delay '0:0:4'--  0.1%, 
                             : 1.2 and sleep  0.1%, 
                             : 1.2scnr_engine_sink_tracer_a6eec1320a29dd8d1494ab94d2c0bc2e  0.0%, 
                             : 1.2scnr_engine_sink_tracer_cd1b14c48e75e2f6354f32a2b5e83c89_abf1b619a817ccf7817092c315227936\  0.0%, 
                             : 1.2scnr_engine_sink_tracer_f378d598dea8d13bf513a9ce9f15b996  0.0%, 
                             : 1.2scnr_engine_sink_tracer_9502768ca4e2db747959749465188b8b  0.0%, 
                             : 1.2scnr_engine_sink_tracer_8647a57ecd36f5b95a850982a5c7f80d  0.0%, 
                             : 1.2scnr_engine_sink_tracer_01f581c65a86c88a93abc31edc4e3c4d_99769d0264bea4fcd0df3cc7374e4e2d\  0.0%.
                             : Unknown 100.0%.
   3.93%           python-requests: 2.27.1 93.4%,  2.32.x  3.7%,  2.31.0  1.4%, 
                             : 2.25.1  0.9%,  2.23.0  0.3%,  2.26.0  0.1%, 
                             : 2.28.1  0.1%,  2.18.4  0.0%,  2.22.0  0.0%, 
                             : 2.6.0 CPython/2.7.5 Linux/3.10.0-1160.119.1.el7.x86_64  0.0%.
                             : Linux  0.0%,  Unknown 100.0%.
   3.46%    4.27%  Firefox   : 111.0  9.0%,  48.0x  7.7%,  133.0  4.4%, 
                             : 121.0  4.3%,  79.0   3.7%,  122.0  3.6%, 
                             : 142.0  3.6%,  123.0x  3.2%,  118.0.2  2.4%, 
                             : 3.5.5  2.4%,  120.0.1  2.3%.
                             : Android  1.5%,  Linux 24.6%,  Macintosh 16.7%, 
                             : SunOS  0.0%,  Unknown  0.3%,  Windows 57.0%.
   3.00%           Go-http-client: 1.1   99.9%,         0.1%.
                             : Unknown 100.0%.
   2.60%    3.21%  Safari    : 605.1x 35.4%,  604.1x 26.9%,  537.36  6.7%, 
                             : 602.4.x  4.8%,  602.1x  4.7%,  530.19x  3.2%, 
                             : 537.85.1x  2.2%,  534.30x  1.7%,  184.1  1.0%, 
                             : 605.6.x  0.7%,  605.5.x  0.5%.
                             : Android  8.3%,  Linux  0.3%,  Macintosh 52.2%, 
                             : SymbianOS  0.1%,  Unknown  1.1%,  Windows  4.7%, 
                             : iPad   4.4%,  iPhone 28.8%,  iPod   0.1%.
   2.10%    2.60%  Netscape  : 5.0x  99.9%,  4.8    0.1%,  4.77   0.0%, 
                             : 3.01Gold  0.0%,  4.0    0.0%.
                             : Android  0.1%,  Linux  0.4%,  Macintosh  0.0%, 
                             : SunOS  0.0%,  Unknown 97.1%,  Windows  2.3%, 
                             : iPhone  0.0%.
   1.94%    2.39%  MSIE      : 9.0   77.0%,  6.0x  10.3%,  10.0   9.5%, 
                             : 7.0x   2.3%,  8.0    0.7%,  5.0    0.2%, 
                             :        0.0%,  5.5    0.0%,  5.00   0.0%, 
                             : 4.01   0.0%,  11.0   0.0%.
                             : Linux  0.0%,  Unknown  0.1%,  Windows 99.9%.
   1.35%           l         : 9explore/1.2.2 99.9%,  9explore/1.0.0  0.1%.
                             : Unknown 100.0%.
   1.15%           Custom-AsyncHttpClient

Notes: MSIE refers to Microsoft Internet Explorer, Netscape refers to Netscape Navigator, SeaMonkey refers to SeaMonkey and to older versions (called the Mozilla Suite). Firefox refers to Mozilla Firefox and to older versions (Mozilla Firebird, Firebird™ and Phoenix). All shows the percentage of accesses using the corresponding user agent, Brwsrs only counts recognized web browsers. A version ending in x refers to multiple sub-versions.

    Misses  Hosts  Originating Domain
     44497   2014  amazonaws.com
     23394    264  in-addr.arpa
     14386      6  45.134.225
     13361      2  159.65.133
     13210      2  193.142.147
     12731      2  143.198.93
      8472      1  159.89.204
      6371     56  cloudwaysapps.com
      5645      1  152.42.239
      5364      1  167.71.231

    Misses  Hosts  Originating Country or Group
    321888  32108  Unknown Origin
     79598   8182  com   - Commercial
     23394    264  arpa
     14769   2025  net   - Network Provider
      5364      1  asia
      1965    175  org   - Non-commercial, non-governmental organization
      1734   1614  br    - Brazil
      1645      1  lk    - Sri Lanka
      1617    214  edu   - Educational
      1281     89  cn    - People's Republic of China

 Lnks  Misses  ...From Links on Host      Most Common Linking Page and Target
 5830   45406  www.ece.lsu.edu            2338 From → /smehraeen/Assets/js/jquery-1.2.6.min.js
    1     625  faculty.csu.edu.cn          All From → /gveronis/edu/gveronis
    1     116  www.facebook.com            All From → /wp-login.php
    1     110  www.lsu.edu                 All From → /eng/ece
    1      47  www.baidu.com               All From → /gveronis/edu/gveronis
    1      31  faculty.lsu.edu             All From → /lpeng/wordpress
   15      15  checks.ecsypno.com            1 From → /phpBB2/viewforum.php
    2      15  www.technologyreview.com      9 From → /bwei/index.html
    1       6  daimajiaoliu.com            All From → /ipl/Teaching.html%C2%A0
    1       6  www.ece.lsu.eduadmin        All From → /module
    6       6  www.semanticscholar.org       1 From → /xinli/Research/XinLiSPM07.pdf
    1       4  www.iogp.org                All From → //xmlrpc.php
    4       4  electronics.stackexchange.com     1 From → /desouza/Classes/EE3950/EE3950 Class Notes Chapter 11.pdf
    1       4  faperta.upr.ac.id           All From → //xmlrpc.php
    1       4  phi.history.ucla.edu        All From → //xmlrpc.php
    1       4  keihoku.kyoto-fsci.or.jp    All From → //xmlrpc.php
    1       3  interact.sh                 All From → /goform/goform_get_cmd_process
    1       3  www.geek-share.com          All From → /hpca-18/files/HPCA2012_Facebook_Keynote
    1       3  130.39.222.33admin          All From → /module
    1       3  users.erols.com             All From → /bwei/webpage.htm

 #e #s #p Misses Using Search Strings...                ...Found Page (Most Misses)
  1  1 468   912  ece /online-degree-programs
  5  1 13    92  wordpress /wp-login.php
  3  1  1    68  SHOW DIAGNOSTICS /query
  1  1  1    32  Set-Cookie content /eng/ece
  1  1  3    12  Computing 3D Shape Guarding and Star Decomposition, https://www.baidu.com/q/xinli/Research/SIG11_Poster.pdf
  1  1  5     6  joomla /administrator
  1  1  1     4  Piecewise surface flattening for non-distorted texture mapping., https://www.baidu.com/q/xinli/Research/TRSphMap2011.pdf
  1  1  1     4  SGP '04, https://www.baidu.com/q /xinli/Data/LiepaSGP2003.pdf
  1  1  1     3  On Computing Mapping of 3D Objects, https://www.baidu.com/q/xinli/Research/Survey_Mapping_CSUR14.pdf
  1  1  2     3  wordpress admin /login
  1  1  1     2  Current Methods in Medical Image Segmentation/gunturk/Topics/Segmentation-1.pdf
  1  2  1     2  Medical Image Segmentation /gunturk/Topics/Segmentation-1.pdf
  1  1  1     2  microsoft catapult torus 6*8 /lpeng/ee7700-2/Chap7.pptx
  1  1  2     2  unsigned+int+to+hex /ee4720/2016/hex-string.s.html&sa=U&ved=2ahUKEwi3t4mZ1M-BAxWSKxAIHVcTAF0QFnoECAAQAg&usg=AOvVaw0i9Sz4v1kqNM1AdrSd3su0
  1  1  1     1  image segmentation /gunturk/Topics/Segmentation-1.pdf
  1  1  1     1  japan tenbu /kak/VedicJapan.pdf
  1  1  1     1  medical image processing methods /gunturk/Topics/Segmentation-1.pdf
  1  1  1     1  opengl+3.2+spec /koppel/gp/refs/glspec32.core.20090803.pdf&sa=U&ved=2ahUKEwilt-m40K2AAxUjGxAIHdUbD-IQFnoECAkQAg&usg=AOvVaw3oT1mdNyj275t-qCsR3P-4
  1  1  1     1  Soft error resilience in Big Data kernels through modular analysis/lpeng/papers/jsc16.pdf
  1  1  1     1  Workers from the Taj Mahal /kak/taj.pdf

#e: Number of different search engines used, link is to the most common engine.
#s: Number of search strings the line actually reports on. For example, if the #s entry were 5 and the string shown were "Computers" the line might report on search strings "Computers", "Computer", "+Computers", "COMPUTERS", and even "-computers".
#p: Number of distinct pages that were missed, the one with the most misses from the string is shown.

Status Codes (Access Outcomes)
  Count Code Description
  38330 400  Syntax error in request.
 207276 403  Forbidden.
1364839 404  Not found.
    310 405  Method not allowed.
    953 408  Request timeout.
    372 416  Range not satisfiable.
      1 417  Unknown status.
   8131 500  Server error.
      1 501  Not implemented.