DAFTAR REFERENSI [CAL03]
CallXpress: Unified Messaging in Today’s Business Environment, A Guide to voice, Fax and Email Anytime, Anywhere. Avst. 2003
[CHA00]
Chai Kiat Yeo, Siu Cheung Hui, Ing Yann Soon, Gupta Manik: Unified Messaging: A System for the Internet, International Journal of the Computer, the Internet and Management, Vol. 8, No. 3, 2000, pp . 1-14
[ETS05]
ETSI: Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); AT command set for User Equipment (UE) (3GPP TS 27.007 version 6.8.0 Release 6). ETSI. 2005
[LOO08]
ASCII Table – ASCII character codes and html, octal, hex and decimal chart conversion. http://www.lookuptables.com. Pengaksesan 18 Juni 2008
[MAN06]
Manaf, A., Zuhri, M.: NoteBOX with Unified Messaging System. Network 2006: 12th international Telecommunication Network Strategy and Planning Symposium, New Delhi, November 6-9-2006
[MAR95]
Margolis, Andrew: Fax Modem Sourcebook. Wiley. 1995
[WEB08][1] Webopodia: AT command set. http://www.webopedia.com/TERM/A/AT_command_set.htm. Pengaksesan 24 Februari 2008 [WEB08][2] Webopodia: gateway. http://www.webopedia.com/TERM/g/gateway.html. Pengaksesan 24 Februari 2008 [WEB08][3] Webopodia: GSM. http://www.webopedia.com/TERM/G/GSM.html. Pengaksesan 24 Februari 2008 [WEB08][4] Webopodia: PSTN. http://www.webopedia.com/TERM/P/PSTN.html. Pengaksesan 24 Februari 2008 [WEB08][5] Webopodia: fax machine. http://www.webopedia.com/TERM/f/fax_machine.html. Pengaksesan 24 Februari 2008 [WIK08][1]
Wikipedia: International Telecommunication Union. http://en.wikipedia.org/wiki/ITU. Pengaksesan 27 Februari 2008
[WIK08][2]
Wikipedia: Integrated Services Digital Network. http://en.wikipedia.org/wiki/ISDN. Pengaksesan 27 Februari 2008 xii
[WIK08][3]
Wikipedia: American National Standads Institute. http://en.wikipedia.org/wiki/American_National_Standards_Institute. Pengaksesan 27 Februari 2008
[WIK08][4]
Wikipedia: Telecommunications Industry Association. http://en.wikipedia.org/wiki/Telecommunications_Industry_Associatio n. Pengaksesan 27 Februari 2008
[WIK08][5]
Wikipedia: Electronic Industry Alliance. http://en.wikipedia.org/wiki/Electronic_Industries_Alliance. Pengaksesan 27 Februari 2008
[WIK08][6]
Wikipedia: Handshaking. http://en.wikipedia.org/wiki/Handshaking. Pengaksesan 27 Februari 2008
[WIK08][7]
Wikipedia: Store and forward. http://en.wikipedia.org/wiki/Store_and_forward. Pengaksesan 28 Februari 2008
[WIK08][8]
Wikipedia: International Organization for Standardization. http://en.wikipedia.org/wiki/International_Organization_for_Standardi zation. Pengaksesan 2 Maret 2008
[WIK08][9]
Wikipedia: Fax. http://en.wikipedia.org/wiki/Fax. Pengaksesan 24 Februari 2008
xiii
DAFTAR PUSTAKA [MAR95]
Margolis, Andrew: Fax Modem Sourcebook. Wiley. 1995
[PEN02]
Pender, Thomas A.: UML Weekend Crash Course. Wiley Publishing, Inc. 2002
[PRE97]
Pressman, Roger S.: Software Engineering (A Practitional’s Approach). McGraw-Hill. 1997
[TAN03]
Tanenbaum, Andrew S.: Computer Networks, Fourth Edition. Prentice Hall, 2003
xiv
LAMPIRAN A Cross Reference Antara Fax Modem Kelas 2 Dengan Fax Modem Kelas 2.0 Berikut adalah cross reference yang bisa digunakan untuk membedakan command antara modem kelas 2 dengan modem kelas 2.0 [MAR95]. Tabel A-1 Class 2/2.0 Action Commands Same Class 2 Class 2.0
Short Description
Yes
ATA
ATA
Answer phone
Yes
ATD
ATD
Originate call (dial )
AT+FDT
AT+FDT
Continue with transmission
AT+FDT=
Transmit with data conversion
AT+FDR
AT+FDR
Continue with reception
AT+FK
AT+FKS
Terminate session
AT+FET=
Send post-page message AT+FIP
Reset fax parameters
Tabel A-2 Class 2/2.0 Parameter Setting Commands Same Opt? Class 2 Opt? Class 2.0
Short Description
Yes
AT+FCLASS?
AT+FCLASS?
Service class
Yes
AT+FMFR?
AT+FMI?
Read only manufacturer ID
Yes
AT+FMDL?
AT+FMM?
Read only modem ID
Yes
AT+FREV
AT+FMR?
Read only revision ID
Yes
AT+FDCC=
AT+FCC=
Modem capabilities
Yes
AT+FDIS=
AT+FID=
Session capabilities
Yes
AT+FDCS=
AT+FCS=
Read only current session parameters
Yes
AT+FLID=
AT+FLI=
Local ID
Yes
AT+FCIG=
AT+FPI=
Polling ID
Yes
AT+FSPL=
AT+FSP=
Request to poll
Yes
AT+FLPL=
AT+FLP=
Document available for polling
Yes
AT+FPTS=
AT+FPS=
Received page transfer status
Yes
AT+FBUG=
AT+FBU=
HDLC frame content reporting
AT+FNR=
Enable negotiation reporting
A-1
AT+FIE=
Enable procedure interrupts
Yes
Yes
AT+FCR=
AT+FLO=
Select flow control
AT+FPR=
Serial port bit rate
AT+FPP=
Packet protocol
Yes
AT+FNS=
Non-standard negotiations
Yes
AT+FCR=
Ability to receive
Begin sending received fax data
Stop sending received fax data and abort
Yes
Yes
AT+FAA=
Yes
AT+FAA=
Adaptive answering
Yes
AT+FBUF?
Yes
AT+FBS?
Read only buffer status
Yes
AT+FTBC
Transmit block size
Yes
AT+FRBC
Receive block size
Yes
AT+FCQ= Yes
Yes
AT+FCQ=
Received quality checking
AT+FRQ=
Receive quality thresholds
AT+FBADMUL=
Acceptable ratio of good/bad lines
Yes
AT+FBADLIN=
Maximum consecutive bad lines
Yes
Yes
AT+FCTCRTY=
Yes
AT+FRY=
Number of CTCs allowed in ECM
Yes
AT+FPHCTO=
Yes
AT+FCT=
Phase C timeout
Yes
Yes
AT+FAXERR
Yes
AT+FHS=
Last hangup status code
Yes
Yes
AT+FMINSP=
Yes
AT+FMS=
Minimum phase C data transfer speed
Yes
AT+FECM
Ability to do error correction
Yes
Yes
AT+FBOR=
AT+FBO=
Bit ordering
Yes
Yes
AT+FREL=
AT+FEA=
EOL alignment
AT+FFC
Mismatch
Yes
checking/conversion Yes
AT+FDFFC=
Check/convert compression formats
Yes
AT+FWDFC=
Check/convert width mismatches
Yes
AT+FLNFC=
Check/convert length mismatches
Yes
AT+FVRFC=
Check/convert resolution mismatches
A-2
AT+FFD=
Set file transfer diagnostic message
AT+FAP
Accept SUB, SEP and PWD
AT+FSA=
Subaddress
AT+FPA
Selective polling address
AT+FPW=
Password
Tabel A-3 Class 2/2.0 Responses and Reports Same Class 2 Class 2.0 Short Description Yes
+FDCS:
+FCS:
Report fax parameters from DCS frame
Yes
+FDIS:
+FIS:
Report fax parameters from DIS frame
Yes
+FDTC:
+FTC:
Report fax parameters from DTC frame
Yes
+FPOLL:
+FPO:
Answering fax is pollable
+FCFR:
CFR sent, prepare to receive data
<xon>
Begin sending fax data for transmission
Yes
+FTSI:
+FTI:
Transmitter’s ID from TSI frame
Yes
+FCSI:
+FCI:
Answerer’s ID from CSI frame
Yes
+FCIG:
+FPI:
Poller’s ID from CIG frame
Yes
+FNSF:
+FNF:
Contents of NSF frame
Yes
+FNSS:
+FNS:
Contents of NSS frame
Yes
+FNSC:
+FNC:
Contents of NSC frame
Yes
+FHT:
+FHT:
Debug report of HDLC frames sent
Yes
+FHR:
+FHR:
Debug report of HDLC frame received
Yes
+FCON
+FCO
Fax connection established
Yes
+FVOICE
+FVO
PRI-Q (transition to voice)
+FDM
Data call detected: reset +FCLASS=0
+FET:
+FET:
Report contents of post-page message
+FPTS:
+FPS:
Received page transfer status
Yes
+FPTS +FHNG:
Transmitted page transfer status +FHS:
Hangup status report
+FFD:
Report FDM file diagnostic message
+FSA:
Report SUB subaddress frame
+FPA:
Report SEP selective polling address
+FPW:
Report PWD password frame
A-3
Tabel A-4 Class 2/2.0 embedded phase C commands Data transparency
One dle (16 decimal, 10h)
<1ah>
Two dle
Transmit commands <2ch>
End of page, return to phase C for another page (MPS)
<3bh>
End of page, return to phase B and renegotiate (EOM)
<2eh>
End of page and session (EOP)
<21h>
Procedure interrupt (PRI-Q)
<3fh>
Request free space in transmit buffer
<etx>
Acknowledge modem abort request
Receive commands <etx>
End of page
<41h>
Embedded <soh> in packet
<57h>
Embedded <etb> in packet
<4fh>
Marker for data loss due to overrun
Transmit format conversion <61h>
Vertical resolution normal
<62h>
Vertical resolution fine
<63h>
A4 length
<64h>
B4 length
<65h>
Unlimited length
<66h>
215 mm width
<67h>
255 mm width
<68h>
313 mm width
<69h>
151 mm width
<6ah>
107 mm width
<6bh>
1-D modified Huffman
<6ch>
2-D modified Read
<6dh>
2-D uncompressed mode
<6eh>
2-D MMR (T.6)
A-4
Receiver buffer status <3fh>
Request free space in transmit buffer
<12h>
Buffer empty
<30h>
Buffer less than 10% full
<31h>
Buffer 10-20% full
<32h>
Buffer 20-30% full
<33h>
Buffer 30-40% full
<34h>
Buffer 40-50% full
<35h>
Buffer 50-60% full
<36h>
Buffer 60-70% full
<37h>
Buffer 70-80% full
<38h>
Buffer 80-90% full
<39h>
Buffer more than 90% full
Tabel A-5 Class 2 +FHNG Status Codes Codes 0-9 are reserved for call placement and termination errors. Only four of these are defined. 0
Normal end of session
1
Call answered without successful fax handshake
2
Call aborted by user (via either +FK or CAN)
3
No Loop Current
Codes 10-19 are reserved for transmit phase A errors. Only two of these are defined. 10
Unspecified phase A error
11
No answer or no DIS detected (T.30 T1 timeout)
Codes 20-39 are reserved for transmit phase B errors. Nine of these are defined. 20
Unspecified error
21
Remote cannot receive or send (bits 9 and 10 in DIS both 0)
22
Command frame error
23
Invalid command received
24
Response frame error
25
DCS sent three times without response
26
DIS/DTC received 3 times; DCS not recognised
27
Failure to train at either 2400 bps or +FMINSP value
28
Invalid rensponse received
A-5
Codes 40-49 are reserved for transmit phase C errors. Only two are defined. 40
Unspecified error
43
DTE to DCE data underflow (data not sent fast enough)
Codes 50-69 are reserved for transmit phase D errors. Nine of these are defined. 50
Unspecified error
51
Response frame error
52
No response to MPS repeated 3 times
53
Invalid response to MPS
54
No response to EOP repeated 3 times
55
Invalid response to EOP
56
No response to EOM repeated 3 times
57
Invalid response to EOM
58
Unable to continue after PIN or PIP
Codes 70-89 are reserved for receive phase B errors. Only five errors are defined. 70
Unspecified error
71
Response frame error
72
Command frame error
73
Expected frame not received (T.30 T2 timeout)
74
Failure to resume phase B after EOM (T.30 T1 timeout)
Codes 90-99 are reserved for receive phase C errors. Four of these are defined. 90
Unpsecified error
91
Missing EOL after 5 seconds (line too long)
93
Modem receive buffer overflowed
94
CR or frame error in ECM or BFT modes
Codes 100-119 are reserved for receive phase D errors. Four codes are defined. 100
Unspecified error
101
Response frame error
102
Command frame error
103
Unable to continue after PIN or PIP
A-6
Tabel A-6 Class 2.0 +FHS Status Codes Codes 00-0F are reserved for call placement and termination errors. Six codes are defined. 04 and 05 are new in Class 2.0 00
Normal end of session
01
Call answered without successful fax handshake
02
Call aborted by user (via either +FK or CAN)
03
No Loop Current
04
Ringback detected, dial attempt timed out with no answer
05
Ringback detected, call answered but without a CED tone
Codes 10-1F are reserved for transmit phase A errors. Only two of these are defined. 10
Unspecified phase A error
11
No answer or no DIS detected (T.30 T1 timeout)
Codes 20-3F are reserved for transmit phase B errors. Nine of these are defined. 20
Unspecified error
21
Remote cannot receive or send (bits 9 and 10 in DIS both 0)
22
Command frame error
23
Invalid command received
24
Response frame error
25
DCS sent three times without response
26
DIS/DTC received 3 times; DCS not recognised
27
Failure to train at either 2400 bps or +FMINSP value
28
Invalid rensponse received
Codes 40-4F are reserved for transmit phase C errors. Eight codes are defined. 40
Unspecified error
41
Unspecified image format
42
Image conversion error
43
DTE to DCE data underflow (data not sent fast enough)
44
Unrecognised command
45
Wrong line length
46
Wrong page length
47
Wrong compression code
A-7
Codes 50-6F are reserved for transmit phase D errors. Nine of these are defined. 50
Unspecified error
51
Response frame error
52
No response to MPS repeated 3 times
53
Invalid response to MPS
54
No response to EOP repeated 3 times
55
Invalid response to EOP
56
No response to EOM repeated 3 times
57
Invalid response to EOM
58
Unable to continue after PIN or PIP
Codes 70-8F are reserved for receive phase B errors. Only five errors are defined. 70
Unspecified error
71
Response frame error
72
Command frame error
73
Expected frame not received (T.30 T2 timeout)
74
Failure to resume phase B after EOM (T.30 T1 timeout)
Codes 90-9F are reserved for receive phase C errors. Four of these are defined. 90
Unpsecified error
91
Missing EOL after 5 seconds (line too long)
93
Modem receive buffer overflowed
94
CR or frame error in ECM or BFT modes
Codes A0-BF are reserved for receive phase D errors. Four codes are defined. A0
Unspecified error
A1
Response frame error
A2
Command frame error
A3
Unable to continue after PIN or PIP
A-8
LAMPIRAN B Daftar Tabel ASCII ASCII merupakan singkatan dari American Standard Code for Information Interchange. Komputer hanya mengenal angka, oleh karena itu kode ASCII adalah representasi angka dari karakter-karakter seperti 'a' atau '@' atau semacam aksi (delete, backspace, dll). Di bawah ini dapat dilihat tabel 256 karakter ASCII termasuk di dalamnya deskripsi 32 karakter non-printing.
B-1
B-2
LAMPIRAN C SKENARIO KEJADIAN
C.1
Skenario Verify Email
Tabel C-1 Skenario Verify E-mail User Aktor Melakukan verifikasi apakah alamat e-mail yang digunakan valid atau Tujuan tidak Halaman native client terbuka Pre-kondisi [normal] E-mail valid dan user masuk ke home page Post-kondisi [alternatif 1] E-mail tidak valid, user tetap berada di halaman login Urutan aksi normal No Pelaku Aksi 1 User Memasukkan alamat e-mail ke field yang tersedia 2 Sistem melakukan validasi e-mail 3 Sistem menampilkan home page Urutan aksi alternatif 1 (gagal menyimpan pesan) 3 Sistem Menampilkan pesan kesalahan
C.2
Skenario Send Query
Tabel C-2 Skenario Send Query User Aktor Mengirim query ke search server NoteBOX Tujuan Home page native client terbuka Pre-kondisi [normal] Query terkirim ke NoteBOX Post-kondisi [alternatif] Menampilkan pesan kesalahan Urutan aksi normal No Pelaku Aksi 1 User Memasukkan query ke field yang disediakan 2 User Memilih tipe pengiriman respon ke faksimili 3 Sistem klik tombol send 4 Sistem menampilkan home page Urutan aksi alternatif 1 (gagal menyimpan pesan) 4 Sistem Menampilkan pesan kesalahan
C-1
C.3
Skenario Request Fax Sending
Tabel C-3 Skenario Request Fax Sending User Aktor Request pengiriman dokumen sebagai pesan faksimili ke nomor tertentu Tujuan Sistem berfungsi Prekondisi [normal] Report pengiriman pesan sampai di ponsel/e-mail user Post kondisi [alternatif] None Urutan aksi normal No Pelaku Aksi 1 User Mengirim pesan SMS dengan kata kunci pengiriman faksimili ke NoteBOX 2 Sistem Mengolah pesan SMS: file yang akan dikirim dan alamat tujuan pengiriman 3 Sistem Mengirimkan pesan faksimili ke remote fax machine 4 Sistem Mengirimkan report pengiriman pesan faksimili: berhasil atau gagal Urutan aksi alternatif (pesan gagal disimpan ke basis data) 2 Sistem Kata kunci salah, tidak mengirimkan respon apapun
C.4
Skenario Send Fax
Tabel C-4 Skenario Send Fax Sistem Aktor Mengirim pesan faksimili ke remote fax machine Tujuan Diterima pesan dari core server untuk pengiriman pesan faksimili Pre-kondisi [normal] pesan faksimili terkirim ke outsider Post-kondisi [alternatif] pesan gagal terkirim Urutan aksi normal No Pelaku Aksi 1 Sistem Membuka dan mengatur koneksi dengan modem faksimili melalui serial port. 2 Sistem Encode dokumen ke format T.4 3 Sistem Melakukan koneksi ke remote fax machine (outsider) 4 Outsider Menerima koneksi 5 Sistem Mengirimkan dokumen dalam bentuk pesan faksimili 6 Sistem Melepas koneksi dan resource dengan modem faksimili Urutan aksi alternatif 1 2 Sistem Dokumen tidak ditemukan, tidak bisa dibaca; pesan gagal 4 Outsider Koneksi ditolak: Line Busy, No Carrier, dll; pesan gagal 5 Sistem Koneksi terputus; pesan gagal
C-2
LAMPIRAN D DIAGRAM SEKUEN
D.1
Diagram Sekuen Verify Email
Gambar D-1 Diagram Sekuen Verify Email
D.2
Diagram Sekuen Send Query
Gambar D-2 Diagram Sekuen Send Query
D-1
D.3
Diagram Sekuen Sending Fax
Core Server
<> : FaxGateway
<> : ModemConnector
<<entity>> : FaxProducer
<> : Codec
SMS Gateway
Email Gateway
Utility
: Outsider 1 : notify()
2 : getMessage() 4 : return message 3 : processMessage() 5 : openConnection() 6 : getModemCapabilities() 7 : return capabilities 9 : convertToT4()
8 : createFax()
12 : connectToOutsider() 11 : return T4 image 10 : return T4 image 13 : return connection accepted 14 : faxHandshake()
15 : return handshake accpeted 16 : sendFax()
17 : fax received, return hang up 18 : saveT4ToTiff()
19 : deleteT4Image()
20 : sendStatus() 21 : sendReport() 22 : sendReport()
Gambar D-3 Diagram Sekuen Sending Fax
D-2
D.4
Diagram Sekuen Send Fax Request SMS Gateway
Core Server
Fax Gateway
: User 1 : sendRequest() 2 : processSMS()
3 : passMessage() 4 : notify()
Gambar D-4 Diagram Sekuen Send Fax Request
D-3
LAMPIRAN E Modified Huffman Coding Modified Huffman Coding digunakan pada mesin faksimili untuk mengkodekan titiktitik hitam pada image putih (bitmaps). Teknik ini menggabungkan teknik kompresi Huffman berdasarkan frekuensi kemunculan dan teknik run-length scheme. Runlength dapat diartikan sebagai panjangnya kemunculan titik-titik hitam dan titik-titik putih secara berturutan pada bitmap pembentuk dokumen faksimili.
Pada gambar E-1 dapat dilihat contoh penggunaan teknik Huffman dalam pemampatan string “this is an example of a huffman tree”. Frekuensi dan kode untuk setiap karakter dapat disimak pada tabel E-1. Mengkodekan pesan tersebut menggunakan teknik Huffman membutuhkan space 135 bit, tanpa space untuk menyimpan pohon Huffman-nya. Root
0
1
0
1
‘e’, 4
1
‘n’, 2
‘a’, 4
1
‘o’, 1
0
1
‘t’, 2
‘u’, 1
1
0
‘m’, 2
‘i’, 2
‘x’, 1
1
1
0
‘h’, 2
‘p’, 1
‘s’, 2
0
‘r’, 1
Gambar E-1 Pohon Huffman dari String “this is an example tree”
E-1
‘ ’, 7
‘f’, 3
‘l’, 1
Tabel E-1 Frekuensi dan Kode dari Pohon Huffman Karakter
Frekuensi
Kode
Space ‘ ‘
7
111
A
4
010
E
4
000
F
3
1101
H
2
1010
I
2
1000
M
2
0111
N
2
0010
S
2
1011
T
2
0110
L
1
11001
O
1
00110
P
1
10011
R
1
11000
U
1
00111
X
1
10010
Modified Huffman Coding digunakan untuk mengkodekan run-length hitam dan putih pada image yang akan dikirim mesin faksimili. Tabel E-2, tabel E-3, dan tabel E-4 menunjukkan kode-kode kompresi Huffman untuk white run-lengths dan black runlengths berdasarkan spesifikasi ITU. Pada tabel tersebut ada dua macam kode: terminating codes, untuk run-lengths dengan panjang 0-63, dan make-up codes yang merupakan kelipatan 64 untuk digunakan dalam pengkodean run-lengths yang lebih panjang.
E-2
Tabel E-2 Terminating Codes run
white
black
run
white
black
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
00110101 000111 0111 1000 1011 1100 1110 1111 10011 10100 00111 01000 001000 000011 110100 110101 101010 101011 0100111 0001100 0001000 0010111 0000011 0000100 0101000 0101011 0010011 0100100 0011000 00000010 00000011 00011010
0000110111 010 11 10 011 0011 0010 000111 000101 0001000 0000100 0000101 0000111 00000100 00000111 000011000 0000010111 0000011000 0000001000 00001100111 00001101000 00001101100 00000110111 00000101000 00000010111 00000011000 000011001010 000011001011 000011001100 000011001101 000001101000 000001101001
32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63
00011011 00010010 00010011 00010100 00010101 00010110 00010111 00101000 00101001 00101010 00101011 00101100 00101101 00000100 00000101 00001010 00001011 01010010 01010011 01010100 01010101 00100100 00100101 01011000 01011001 01011010 01011011 01001010 01001011 00110010 00110011 00110100
000001101010 000001101011 000011010010 000011010011 000011010100 000011010101 000011010110 000011010111 000001101100 000001101101 000011011010 000011011011 000001010100 000001010101 000001010110 000001010111 000001100100 000001100101 000001010010 000001010011 000000100100 000000110110 000000111000 000000100111 000000101000 000001011000 000001011001 000000101011 000000101100 000001011010 000001100110 000001100111
E-3
Tabel E-3 Make-up Codes run
white
black
run
white
black
64 128 192 256 320 384 448 512 576 640 704 768 832 896
11011 10010 010111 0110111 00110110 00110111 01100100 01100101 01101000 01100111 011001100 011001101 011010010 011010011
0000001111 000011001000 000011001001 000001011011 000000110011 000000110100 000000110101 0000001101100 0000001101101 0000001001010 0000001001011 0000001001100 0000001001101 0000001110010
960 1024 1088 1152 1216 1280 1344 1408 1472 1536 1600 1664 1728
011010100 011010101 011010110 011010111 011011000 011011001 011011010 011011011 010011000 010011001 010011010 011000 010011011
0000001110011 0000001110100 000000111010 0000001110110 0000001110111 0000001010010 0000001010001 0000001010100 0000001010101 0000001011010 0000001011011 0000001100100 0000001100101
Tabel E-4 End Of Line Code EOL Code word 000000000001
E-4
LAMPIRAN F 1-D Coding Scheme ITU-T.4
Coding scheme yang digunakan dalam pembangunan prototype fax gateway ini adalah 1-D coding scheme. 1-D run length coding scheme yang direkomendasikan untuk mesin-mesin faksimili grup 3 adalah seperti keterangan berikut ini.
F.1
Data
Setiap baris data disusun oleh kumpulan variable length code words. Setiap code word merepresentasikan run-length baik white run-length maupun black run-length. White runs dan black runs saling bergantian. Lebar dokumen 215 mm dinyatakan sebagai 1728 picture elements (titik) merepresentasikan satu scan line horizontal.
Untuk memastikan bahwa mesin penerima menjaga colour synchronization, semua baris data diawali dengan white run-length code word. Jika scan line yang sebenarnya dimulai degan black run, maka white run length nol akan dikirimkan. Run-length hitam dan putih dapat dilihat pada lampiran E. Ada dua macam code words: terminating code words dan make-up code words. Setiap run-length dinyatakan dengan sebuah terminating code word atau sebuah make-up code word diikuti dengan sebuah terminating code word.
Run-length pada cakupan 0 sampai 63 dikodekan dengan terminating code word masing-masing yang bersesuaian. Run-length dalam cakupan 64 sampai 1728 dikodekan dulu dengan make-up code word yang menyatakan run-length yang nilainya sama atau kurang dari yang dibutuhkan. Lalu diikuti oleh terminating code word yang menyatakan perbedaan antara run-length yang dibutuhkan dengan runlength yang diwakili dengan make-up code.
F-1
F.2
End-of-Line (EOL)
Code word ini selalu mengikuti setiap baris data. EOL merupakan code word yang unik yang tidak akan bisa ditemukan dalam baris data yang valid. EOL ini akan dikirmkan juga sebelum baris data pertama dari sebuah halaman. Format EOL yaitu: 000000000001
F.3
Fill
Penundaan (pause) bisa saja diletakkan pada aliran pesan dengan mentransmisikan “fill”. Fill dapat disisipkan antara baris data dan EOL, tapi tidak boleh disisipkan di dalam baris data. Fill harus ditambahkan untuk memastikan waktu transmisi data, fill dan EOL tidak kurang dari waktu transmisi minimum dari total coded scan line pada pre-message control procedure. Waktu transmisi maksimum fill bits harus kurang dari 5 detik. Format fill: variable length string of 0s.
F.4
Return To Control (RTC)
Akhir dari transmisi dokumen diindikasikan dengan pengiriman enam EOL berturutan. Setelah sinyal RTC, transmitter akan mengirimkan frame post message commands. Format: 000000000001 . . . . . . . . . . 000000000001 (total 6 kali)
Gambar F-1 dan gambar F-2 akan menjelaskan hubungan sinyal yang dinyatakan pada lampiran ini. Gambar F-1 menunjukkan beberapa scan line data dimulai pada permulaan halaman yang ditransmisikan. Gambar 2 menjelaskan kode scan line terakhir dari sebuah halaman.
Gambar F-1 Permulaan pengiriman scan line data
F-2
Gambar F-2 Akhir pengiriman data
F-3
