Computer Network Research Group ITB Beginners Guide to Internet Onno W. Purbo Institute of Technology Bandung.

Presentasi berjudul: "Computer Network Research Group ITB Beginners Guide to Internet Onno W. Purbo Institute of Technology Bandung."— Transcript presentasi:

1 Computer Network Research Group ITB Beginners Guide to Internet Onno W. Purbo Institute of Technology Bandung

2 Computer Network Research Group ITB Outline l Objective –Menerangkan secara praktis ttg. Internet l Outline –Teknologi Komunikasi & Komputer –Berbagai Aplikasi Internet

3 Computer Network Research Group ITB Distribusi Registrasi Domain Internet

4 Computer Network Research Group ITB Indonesia Internet Topology

5 Computer Network Research Group ITB Indonesia Internet Topology Hubungan Ke Internet 10 Mbps

6 Computer Network Research Group ITB Indonesia Internet Topology Banyak Jaringan Regional Yang Tumpang Tindih

7 Computer Network Research Group ITB Indonesia Internet Topology Network Packet Radio Merupakan Jaringan Pertama Internet Indonesia Terutama masuk ke LAPAN & ITB

8 Computer Network Research Group ITB Indonesia Internet Topology ITB Menjalankan Backbone Asia Pasifik Yang Pertama 2Mbps

9 Computer Network Research Group ITB Indonesia Speed To Internet Year bps (log plot)

10 Computer Network Research Group ITB Indonesia Speed To Internet Year bps (log plot) Naik Secara Exponensial!

11 Computer Network Research Group ITB Indonesia Speed To Internet Year bps (log plot) Harus Membangun: + Komunitas / User + Backbone Nasional Untuk terus exponensial!

12 Computer Network Research Group ITB Akses ke Internet l IPTEK-NET kecepatan akses 256 Kbps. l IndoInternet kecepatan akses 512Kbps. l RADNet - kecepatan 1.5Mbps. l Sistelindo - kecepatan 768Kbps. l CBN-Net - kecepatan 2Mbps. l D.Net - Kecepatan 2Mbps. l ITB - kecepatan 1.5Mbps (27 September 1996).

13 Computer Network Research Group ITB Teknologi Jaringan Internet l TCP/IP Protocol –Kunci pada IP ADDRESS l Teknologi perangkat keras & perangkat lunak yang banyak dipasaran. l sebagian software public domain. l Tidak tergantung jenis saluran komunikasi.

14 Computer Network Research Group ITB Teknologi Komunikasi Jarak Jauh l Telepon & Leased Line (PT. Telkom). l DOV (PT. Lintas Arta) l SKDP (PT. Lintas Arta). l VSAT (PT. Elektrindo Nusantara, PT. CSM, PT. Lintas Arta & PT. CMI). l Beberapa Alternatif yang murah: –Packet Radio Network –SISDIKSAT via Palapa.

15 Computer Network Research Group ITB Persyaratan PC l Sebaiknya dapat menggunakan Window l Minimal 386 sebaiknya 486. l Memory minimal 8Mbyte l Ada pengecualian untuk PC Packet Radio - dapat digunakan XT!

16 Computer Network Research Group ITB Konfigurasi Hardware l Melalui Packet Radio l Melalui Wireless LAN l Melalui Satelit l Melalui Telepon l Melalui Local Area Network

17 Computer Network Research Group ITB Parameter Penentu l Harga l Kecepatan Pengiriman Data l Jarak Jangkau

18 Computer Network Research Group ITB Konfigurasi Packet Radio XT! Total investasi diluar PC: Modem RadioRp. 150.000 s/d Rp. 800.000,- RadioRp. 225.000 s/d Rp. 3.000.000,- Kec. Max.9600bps (bisa naik ke 256Kbps) Jarak Max.100km

19 Computer Network Research Group ITB Konfigurasi Wireless LAN Wireless LAN Card Inside 2Mbps Total investasi diluar komputer (PC) Wireless LAN US$4000 / buah Kecepatan Max.2Mbps (bisa naik ke 10Mbps) Jarak Max.15 km

20 Computer Network Research Group ITB Konfigurasi Satellite Network Investasi diluar komputer (PC): Sewa peralatan & saluran satelit VSAT SCPCUS$5500 / bulan / 64Kbps VSAT TDMAUS$1500 / bulan / 64Kbps sebaiknya UNIX

21 Computer Network Research Group ITB Konfigurasi Telepon Network Konfigurasi yang umumnya digunakan pengguna Internet Service Provider (ISP) di Indonesia Investasi diluar komputer (PC): Modem TeleponRp. 250.000 s/d Rp. 3.000.000,- Kec. Max.28.8Kbps

22 Computer Network Research Group ITB Konfigurasi Local Area Network Investasi diluar komputer (PC): Ethernet cardRp. 90.000 s/d Rp. 500.000 Kabel dan Hub Ethernet Kec. Max.10-100Mbps. Jarak Max. 500 meter

23 Computer Network Research Group ITB Cara Paling Ekonomis? l Internet baru akan menguntungkan jika berlangganan secara kolektif. l Satu kampus dapat dihubungkan ke Internet dengan satu buah leased-line / saluran komunikasi. l Biaya berlangganan bagi 6-10 orang / bulan bisa membiayai langganan satu kampus selama satu bulan!

24 Computer Network Research Group ITB Cara Paling Ekonomis? l Internet baru akan menguntungkan jika berlangganan secara kolektif. l Satu kampus dapat dihubungkan ke Internet dengan satu buah leased-line / saluran komunikasi. l Biaya berlangganan bagi 6-10 orang / bulan bisa membiayai langganan satu kampus selama satu bulan! Seringkali Kita Tidak Menyadari Hal ini

25 Computer Network Research Group ITB Frequently Asked Questions? l Bagaimana cara menyambungkan sebuah Corporate Wide Area Network? l Peralatan apa saja yang dibutuhkan? l Bagaimana konfigurasi peralatan tersebut?

26 Computer Network Research Group ITB Corporate / Campus Internet

27 Computer Network Research Group ITB Corporate / Campus Internet LAN Di Dalam Universitas Tidak Perlu di Ubah

28 Computer Network Research Group ITB Corporate / Campus Internet Hanya Perlu Penambahan Software

29 Computer Network Research Group ITB Corporate / Campus Internet Firewall / Proxy 486/586 Untuk: Security & Penghematan IP Address

30 Computer Network Research Group ITB Corporate / Campus Internet Bisa Memilih Antara 3 Alternatif

31 Computer Network Research Group ITB Corporate / Campus Internet VSAT TDMA US$ 1500 / month 64Kbps

32 Computer Network Research Group ITB Corporate / Campus Internet WaveLAN 2Mbps - 15 km US$4000 / node

33 Computer Network Research Group ITB Corporate / Campus Internet Sewa Leased Line Telkom / Lintasarta

34 Computer Network Research Group ITB Beberapa Servis Internet l e-mailcnrg@itb.ac.id. l mailing listsysop-l@itb.ac.id l News servernews.ee.itb.ac.id. l WWW http://www.itb.ac.id. l FTP serverftp.ee.itb.ac.id. l Videoconference- l Internet FAX Server- l Internet Phone-

35 Computer Network Research Group ITB Beberapa Servis Internet l e-mailcnrg@itb.ac.id. l mailing listsysop-l@itb.ac.id l News servernews.ee.itb.ac.id. l WWW http://www.itb.ac.id. l FTP serverftp.ee.itb.ac.id. l Videoconference- l Internet FAX Server- l Internet Phone- Ada Lebih Dari 30.000 Kelompok Diskusi di Internet

36 Computer Network Research Group ITB Beberapa Servis Internet l e-mailcnrg@itb.ac.id. l mailing listsysop-l@itb.ac.id l News servernews.ee.itb.ac.id. l WWW http://www.itb.ac.id. l FTP serverftp.ee.itb.ac.id. l Videoconference- l Internet FAX Server- l Internet Phone- Ada Ratusan Virtual Library di Internet

37 Computer Network Research Group ITB Beberapa Servis Internet l e-mailcnrg@itb.ac.id. l mailing listsysop-l@itb.ac.id l News servernews.ee.itb.ac.id. l WWW http://www.itb.ac.id. l FTP serverftp.ee.itb.ac.id. l Videoconference- l Internet FAX Server- l Internet Phone- Ada Ribuan FTP Server Membawa Banyak File

38 Computer Network Research Group ITB Beberapa Servis Internet l e-mailcnrg@itb.ac.id. l mailing listsysop-l@itb.ac.id l News servernews.ee.itb.ac.id. l WWW http://www.itb.ac.id. l FTP serverftp.ee.itb.ac.id. l Videoconference- l Internet FAX Server- l Internet Phone- Ratusan Reflector Telah Dipasang di Internet (termasuk di ITB) Video Conference Melalui Internet - Rp. 7000 / jam - 64Kbps! (Investasi Multimedia PC + US$150)

39 Computer Network Research Group ITB Beberapa Servis Internet l e-mailcnrg@itb.ac.id. l mailing listsysop-l@itb.ac.id l News servernews.ee.itb.ac.id. l WWW http://www.itb.ac.id. l FTP serverftp.ee.itb.ac.id. l Videoconference- l Internet FAX Server- l Internet Phone- Puluhan FAX Server di Internet Dapat di akses melalui E-mail & mengirimkan FAX ke seluruh dunia.

40 Computer Network Research Group ITB Beberapa Servis Internet l e-mailcnrg@itb.ac.id. l mailing listsysop-l@itb.ac.id l News servernews.ee.itb.ac.id. l WWW http://www.itb.ac.id. l FTP serverftp.ee.itb.ac.id. l Videoconference- l Internet FAX Server- l Internet Phone- Menelepon Ke Seluruh Dunia Via Interet -Tanpa SLI Kebutuhan MultiMedia PC + Mic

41 Computer Network Research Group ITB Internet in Windows

42 Computer Network Research Group ITB Internet in Windows Winsock Untuk Mendial ke ISP

43 Computer Network Research Group ITB Internet in Windows Eudora E-mail client

44 Computer Network Research Group ITB Internet in Windows Pegasus Mail E-mail client

45 Computer Network Research Group ITB Internet in Windows Netscape Web Browser

46 Computer Network Research Group ITB Internet in Windows FTP File Transfer Facility

47 Computer Network Research Group ITB Dial ke ISP

48 Computer Network Research Group ITB Dial ke ISP Gunakan Dialer Untuk dial & Disconnect

49 Computer Network Research Group ITB Dial ke ISP Gunakan “File” Untuk mengatur setup Winsock

50 Computer Network Research Group ITB Contoh Setup Winsock

51 Computer Network Research Group ITB Contoh Setup Winsock IP Address PC yang kita gunakan

52 Computer Network Research Group ITB Contoh Setup Winsock IP Address Name Server dari ISP

53 Computer Network Research Group ITB Contoh Setup Winsock No. Port Komunikasi di PC yang kita gunakan

54 Computer Network Research Group ITB Contoh Setup Winsock Kecepatan Port Komunikasi di PC yang kita gunakan

55 Computer Network Research Group ITB Electronic Mail

56 Computer Network Research Group ITB Contoh E-mail Received: from MAILQUEUE by SYSTEM (Mercury 1.12); Mon, 27 Feb 95 10:31:58 +0700 Return-path: From: Received: from mail-in.un.org(157.150.191.1) by internet.un.org via smap (V1.3) id sma018449; Sun Feb 26 21:16:38 1995 Date: Mon, 27 Feb 95 09:19:09 EST Message-Id: To: yc1dav@system.paume.itb.ac.id Subject: Let's meet in Bangkok Dear Onno, Thanks a lot for your response to my inquiry on Indonesian IT development in the public sector. Thanks also for the status report, which I read with great interest. Looking forward to meeting you. Ilpo.

57 Computer Network Research Group ITB Contoh E-mail Received: from MAILQUEUE by SYSTEM (Mercury 1.12); Mon, 27 Feb 95 10:31:58 +0700 Return-path: From: Received: from mail-in.un.org(157.150.191.1) by internet.un.org via smap (V1.3) id sma018449; Sun Feb 26 21:16:38 1995 Date: Mon, 27 Feb 95 09:19:09 EST Message-Id: To: yc1dav@system.paume.itb.ac.id Subject: Let's meet in Bangkok Dear Onno, Thanks a lot for your response to my inquiry on Indonesian IT development in the public sector. Thanks also for the status report, which I read with great interest. Looking forward to meeting you. Ilpo. Header E-mail

58 Computer Network Research Group ITB Contoh E-mail Received: from MAILQUEUE by SYSTEM (Mercury 1.12); Mon, 27 Feb 95 10:31:58 +0700 Return-path: From: Received: from mail-in.un.org(157.150.191.1) by internet.un.org via smap (V1.3) id sma018449; Sun Feb 26 21:16:38 1995 Date: Mon, 27 Feb 95 09:19:09 EST Message-Id: To: yc1dav@system.paume.itb.ac.id Subject: Let's meet in Bangkok Dear Onno, Thanks a lot for your response to my inquiry on Indonesian IT development in the public sector. Thanks also for the status report, which I read with great interest. Looking forward to meeting you. Ilpo. Informasi Seperti: - Dari Siapa? - Subject? - Tanggal & Jam Pengiriman? - Melalui Mesin Mana?

59 Computer Network Research Group ITB Contoh E-mail Received: from MAILQUEUE by SYSTEM (Mercury 1.12); Mon, 27 Feb 95 10:31:58 +0700 Return-path: From: Received: from mail-in.un.org(157.150.191.1) by internet.un.org via smap (V1.3) id sma018449; Sun Feb 26 21:16:38 1995 Date: Mon, 27 Feb 95 09:19:09 EST Message-Id: To: yc1dav@system.paume.itb.ac.id Subject: Let's meet in Bangkok Dear Onno, Thanks a lot for your response to my inquiry on Indonesian IT development in the public sector. Thanks also for the status report, which I read with great interest. Looking forward to meeting you. Ilpo. Isi Berita Ada Di Bawah Header

60 Computer Network Research Group ITB Contoh E-mail Received: from MAILQUEUE by SYSTEM (Mercury 1.12); Mon, 27 Feb 95 10:31:58 +0700 Return-path: From: Received: from mail-in.un.org(157.150.191.1) by internet.un.org via smap (V1.3) id sma018449; Sun Feb 26 21:16:38 1995 Date: Mon, 27 Feb 95 09:19:09 EST Message-Id: To: yc1dav@system.paume.itb.ac.id Subject: Let's meet in Bangkok Dear Onno, Thanks a lot for your response to my inquiry on Indonesian IT development in the public sector. Thanks also for the status report, which I read with great interest. Looking forward to meeting you. Ilpo. Text Yang Dikirim Berupa ASCII atau Attachment File

61 Computer Network Research Group ITB E-mail address yc1dav@cnrg.itb.ac.id yc1davNama User @“at” (bahasa Inggris) cnrg.itb.ac.idNama Mesin

62 Computer Network Research Group ITB E-mail address yc1dav@cnrg.itb.ac.id kode negara, contoh:.id = Indonesia.uk = Inggris.us = Amerika Serikat.jp = Jepang.au = Australia.sg = Singapura

63 Computer Network Research Group ITB E-mail address yc1dav@cnrg.itb. ac.id Kode Jenis Institusi, contoh:.ac. = Academic.co. = Komersial.go. = Pemerintah.or. = Organisasi lainnya, seperti LSM.net. = Internet Service Provider

64 Computer Network Research Group ITB E-mail address yc1dav@cnrg. itb.ac.id Nama Institusi, contoh:.itb.Institut Teknologi Bandung.ui.Universitas Indonesia.bppt. BPPT.ptme PT. Metrodata Elektronik.republika.Koran Republika

65 Computer Network Research Group ITB E-mail address yc1dav@ cnrg.itb.ac.id Nama Mesin atau Sub-Institusi CNRGComputer Network Research Group

66 Computer Network Research Group ITB Konsekuensi Budaya E-mail l Effisiensi Komunikasi. l Komunikasi Tertulis (bukan lisan). l Perkuat kebijaksanaan (kekuatan arus bawah) l Debirokratisasi. l Keterbukaan. l Tidak ada batas institusi. l Penguasaan Pasar.

67 Computer Network Research Group ITB News Browser

68 Computer Network Research Group ITB Nama News Group comp.society.future Berbeda dengan E-mail, “root” berada di sebelah kanan - dalam contoh diatas yang menjadi “root” adalah kelompok “comp”

69 Computer Network Research Group ITB Contoh “Root” Newsgroup l compberbagai diskusi ttg. Computer l sciberbagai diskusi ttg. Science l recberbagai diskusi ttg. Recreation l bizberbagai diskusi ttg. Bisnis l socberbagai diskusi ttg. Social aspect l idberbagai diskusi di Indonesia.

70 Computer Network Research Group ITB Contoh Tampilan News Newsgroups: soc.college,soc.college.grad Subject: FAQ: Financial Aid [Monthly posting] From: mkant+@cs.cmu.edu (Mark Kantrowitz) Date: 13 Jul 1995 07:04:31 GMT Organization: CS, Carnegie Mellon University Financial Aid FAQ Written by Mark Kantrowitz This FAQ may be obtained by anonymous ftp from ftp.cs.cmu.edu [128.2.206.173] in the directory /afs/cs.cmu.edu/user/mkant/public/finaid/finaid.faq using username "anonymous" and password "name@host" (substitute your email address). The FAQ postings are also archived in the periodic posting archive on rtfm.mit.edu:/pub/usenet/news.answers/college/[18.181.0.24] Please mail comments, corrections, additions, suggestions, criticisms and other information to mkant@cs.cmu.edu.

71 Computer Network Research Group ITB Contoh Tampilan News Newsgroups: soc.college,soc.college.grad Subject: FAQ: Financial Aid [Monthly posting] From: mkant+@cs.cmu.edu (Mark Kantrowitz) Date: 13 Jul 1995 07:04:31 GMT Organization: CS, Carnegie Mellon University Financial Aid FAQ Written by Mark Kantrowitz This FAQ may be obtained by anonymous ftp from ftp.cs.cmu.edu [128.2.206.173] in the directory /afs/cs.cmu.edu/user/mkant/public/finaid/finaid.faq using username "anonymous" and password "name@host" (substitute your email address). The FAQ postings are also archived in the periodic posting archive on rtfm.mit.edu:/pub/usenet/news.answers/college/[18.181.0.24] Please mail comments, corrections, additions, suggestions, criticisms and other information to mkant@cs.cmu.edu. Header News Pengirim, Subject, Tanggal dll.

72 Computer Network Research Group ITB Contoh Tampilan News Newsgroups: soc.college,soc.college.grad Subject: FAQ: Financial Aid [Monthly posting] From: mkant+@cs.cmu.edu (Mark Kantrowitz) Date: 13 Jul 1995 07:04:31 GMT Organization: CS, Carnegie Mellon University Financial Aid FAQ Written by Mark Kantrowitz This FAQ may be obtained by anonymous ftp from ftp.cs.cmu.edu [128.2.206.173] in the directory /afs/cs.cmu.edu/user/mkant/public/finaid/finaid.faq using username "anonymous" and password "name@host" (substitute your email address). The FAQ postings are also archived in the periodic posting archive on rtfm.mit.edu:/pub/usenet/news.answers/college/[18.181.0.24] Please mail comments, corrections, additions, suggestions, criticisms and other information to mkant@cs.cmu.edu. Isi News ASCII atau File Attachment

73 Computer Network Research Group ITB File Transfer Protocol

74 Computer Network Research Group ITB Video Tele-conference

75 Computer Network Research Group ITB Konfigurasi TeleConference

76 Computer Network Research Group ITB Konfigurasi TeleConference Multimedia PC

77 Computer Network Research Group ITB Konfigurasi TeleConference Kamera QuickCam US$100-150

78 Computer Network Research Group ITB Konfigurasi TeleConference Akses Internet 64Kbps Menjadikan Total Biaya Rp. 7000 / jam

79 Computer Network Research Group ITB Internet FAX

80 Computer Network Research Group ITB Internet FAX E-mail dikirim ke FAX Server Internet

81 Computer Network Research Group ITB Internet FAX E-mail di terima FAX Server & Di konversikan ke FAX

82 Computer Network Research Group ITB Internet FAX FAX Server Mengirimkan Berita Ke FAX

83 Computer Network Research Group ITB Internet FAX Berita Diterima di FAX Penerima

84 Computer Network Research Group ITB Internet Phone

85 Computer Network Research Group ITB Internet Phone PC Multimedia + Soundblaster

86 Computer Network Research Group ITB Internet Phone Mic & Speaker

87 Computer Network Research Group ITB Internet Phone Client di ISP Mendial Melalui Internet

88 Computer Network Research Group ITB Internet Phone Hubungan Telepon dilakukan ke Telepon Lokal di Luar Negeri

89 Computer Network Research Group ITB WWW Browser

90 Computer Network Research Group ITB WWW Browser Anda dapat meng- “click” pada kata-kata yang berwarna biru untuk memperoleh informasi selanjutnya

91 Computer Network Research Group ITB WWW Browser Lokasi Informasi URL = Universal Resource Locater

92 Computer Network Research Group ITB URL Universal Resource Locater http://www.itb.ac.id/cnrg/collaboration.html

93 Computer Network Research Group ITB URL Universal Resource Locater http ://www.itb.ac.id/cnrg/collaboration.html Protokol yang digunakan untuk berbicara httpHyper Text Transport Protocol (Web) ftpFile Transfer Protocol newsNetwork News Transport Protocol

94 Computer Network Research Group ITB URL Universal Resource Locater http://www.itb.ac.id/cnrg/collaboration.html nama mesin....... ingat penjelasan E-mail address?

95 Computer Network Research Group ITB URL Universal Resource Locater http://www.itb.ac.id/cnrg/collaboration.html file dimana informasi diletakan untuk masuk ke “root” atau “index” perpanjangan ini tidak perlu dilakukan

96 Computer Network Research Group ITB Navigasi Informasi l Melakukan Searching Informasi. l Mengetahui Keyword Informasi yang dibutuhkan.

97 Computer Network Research Group ITB Search Engine Internet l http://www.opentext.com/ l http://www.yahoo.com/ l http://www.altavista.digital.com/ l http://www.lycos.com/ l http://www.webcrawler.com/ l http://inktomi.cs.berkeley.edu/ l http://www.dejanews.com/

98 Computer Network Research Group ITB Contoh Search Lycos

99 Computer Network Research Group ITB Contoh Search Lycos Tempat Memasukan Keyword Keyword Dapat Lebih Dari Satu

100 Computer Network Research Group ITB Contoh Search Lycos Option Untuk Operasi Searching

101 Computer Network Research Group ITB Asia Internet Interconnection Initiatives (AI3) l Multicast Backbone (MBONE) l IP Version 6 (the Next Generation) l Real Time Backbone. l Dynamic Configuration & Routing. l Many Multimedia Traffic. –Video On Demand. –Multimedia on Demand. –Video Teleconferences.

102 Computer Network Research Group ITB Asia Internet Interconnection Initiatives (AI3) l Multicast Backbone (MBONE) l IP Version 6 (the Next Generation) l Real Time Backbone. l Dynamic Configuration & Routing. l Many Multimedia Traffic. –Video On Demand. –Multimedia on Demand. –Video Teleconferences. Major Application Will Be Virtual University - Initiated By United Nation University, Tokyo, Japan Others also very much welcome.

103 Computer Network Research Group ITB Asia Internet Interconnection Initiatives (AI3)

104 Computer Network Research Group ITB Asia Internet Interconnection Initiatives (AI3) Major Hub in Nara, Japan into WIDE Project

105 Computer Network Research Group ITB Asia Internet Interconnection Initiatives (AI3) Asia Pacific Partners, Indonesia, Thailand, Hongkong, Malaysia, Singapore, VietNam, Cambodia, Korea & Japan

106 Computer Network Research Group ITB Asia Internet Interconnection Initiatives (AI3) There is effort to deploy Advanced Asia Pacific Internet Backbone Running at 155Mbps...

107 Computer Network Research Group ITB

108 BAPPEDA ke Internet Melalui ITB pada 2Mbps

109 Computer Network Research Group ITB Dearah Dapat Terhubung Melalui Satelit

110 Computer Network Research Group ITB Daerah Tingkat II Dapat Membangun Network Untuk Membangun Pembangunan

111 Computer Network Research Group ITB Apa Yang Perlu Disiapkan? l Komputer Hanya PC Biasa. l Sumber Daya Manusia (SDM) yang bisa menggunakan komputer (PC) + Windows. l Koordinasi dengan organisasi di sekitarnya. l Bantuan Teknis dari Lembaga Pendidikan.

112 Computer Network Research Group ITB Anda Kesulitan? l Tanya ke Provider.... l Ada beberapa mailing list Indonesia yang sifatnya teknis pau-mikro@ee.umanitoba.ca sysop-l@itb.ac.id

113 Computer Network Research Group ITB Let’s Surf the Internet

114 Computer Network Research Group ITB

115