Path: csiph.com!newsfeed.hal-mli.net!feeder3.hal-mli.net!newsfeed.hal-mli.net!feeder1.hal-mli.net!newsfeed.xs4all.nl!newsfeed2.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.124 X-Spam-Level: * X-Spam-Evidence: '*H*': 0.75; '*S*': 0.00; '16,': 0.03; 'assuming': 0.09; 'credentials,': 0.09; 'cc:addr:python-list': 0.11; 'jan': 0.12; 'disconnect': 0.16; 'governed': 0.16; 'half.': 0.16; 'letting': 0.16; 'received:mac.com': 0.16; 'ssh,': 0.16; 'tcp': 0.16; 'wing': 0.16; 'subject:python': 0.16; 'wrote:': 0.18; '(not': 0.18; 'received:10.0.1': 0.19; 'thu,': 0.19; '>>>': 0.22; 'cc:addr:python.org': 0.22; 'cc:2**1': 0.23; '(or': 0.24; '15,': 0.26; 'chris': 0.29; 'am,': 0.29; "i'm": 0.30; 'url:mailman': 0.30; 'credentials': 0.31; 'ray': 0.31; 'another': 0.32; 'open': 0.33; 'url:python': 0.33; 'connection': 0.35; 'but': 0.35; 'picking': 0.36; 'done': 0.36; 'url:listinfo': 0.36; 'charset:us- ascii': 0.36; 'received:10.0': 0.36; 'url:org': 0.36; 'half': 0.37; 'received:10': 0.37; 'server': 0.38; 'connections': 0.38; 'mine': 0.38; 'received:17': 0.38; 'handle': 0.38; 'resource': 0.38; 'bad': 0.39; "couldn't": 0.39; 'extremely': 0.39; 'sure': 0.39; 'url:mail': 0.40; 'solve': 0.60; 'introduced': 0.61; 'such': 0.63; 'to:addr:gmail.com': 0.65; 'minutes': 0.67; 'between': 0.67; 'gathering': 0.68; 'internet': 0.71; 'carefully': 0.74; 'yourself': 0.78; 'invitation': 0.79; 'protect': 0.79; 'friend': 0.79; 'william': 0.81; '2014,': 0.84; 'break.': 0.84; 'closes': 0.84; 'frustrating': 0.84; 'header:In-reply-to:1': 0.84; 'holes': 0.84; 'off,': 0.84; 'presumption': 0.84 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.11.87,1.0.14,0.0.0000 definitions=2014-01-15_05:2014-01-15,2014-01-15,1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 suspectscore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=7.0.1-1308280000 definitions=main-1401150099 Content-type: text/plain; charset=us-ascii MIME-version: 1.0 (Mac OS X Mail 6.6 \(1510\)) Subject: Re: Learning python networking From: William Ray Wing In-reply-to: Date: Wed, 15 Jan 2014 11:43:41 -0500 Content-transfer-encoding: quoted-printable References: <22d58d76-f2c2-4a1d-8049-3409ac4665d3@googlegroups.com> <9202d352-e065-4f2b-a9e0-e29ce5c68df6@googlegroups.com> <7B721FFF-5F01-4736-AC82-B5E71848F926@mac.com> To: Chris Angelico X-Mailer: Apple Mail (2.1510) Cc: "python-list@python.org" , William Ray Wing X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 39 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1389804229 news.xs4all.nl 2862 [2001:888:2000:d::a6]:33245 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:63998 On Jan 15, 2014, at 11:31 AM, Chris Angelico wrote: > On Thu, Jan 16, 2014 at 3:25 AM, William Ray Wing wrote: >> On Jan 15, 2014, at 7:52 AM, Chris Angelico wrote: >>> One of the fundamentals of the internet is that connections *will* >>> break. A friend of mine introduced me to Magic: The Gathering via a >>> program that couldn't handle drop-outs, and it got extremely >>> frustrating - we couldn't get a game going. Build your server such >>> that your clients can disconnect and reconnect, and you protect >>> yourself against half the problem; allow them to connect and kick = the >>> other connection off, and you solve the other half. >>=20 >> But note VERY carefully that this can open HUGE security holes if not = done with extreme care. >>=20 >> Leaving a dangling connection (not session, TCP closes sessions) open = is an invitation so bad things happening. >=20 > Not sure what you mean here. I'm assuming an authentication system > that stipulates one single active connection per authenticated user > (if you reauthenticate with the same credentials, it'll disconnect the > other one on the presumption that the connection's been lost). In > terms of resource wastage, there's no difference between disconnecting > now and letting it time out, and waiting the ten minutes (or whatever) > and then terminating cleanly. Or do you mean another user gaining > access? It's still governed by the same authentication. >=20 I was assuming another user picking up the connection using sniffed = credentials (and yes, despite all the work on ssh, not all = man-in-the-middle attacks have been killed). -Bill > ChrisA > --=20 > https://mail.python.org/mailman/listinfo/python-list