Judul: Keragaman Komunitas Arthropoda pada Lumut Epifit di Kebun Raya Bogor
Abstrak: Lumut memainkan peran penting bagi kehidupan bryofauna, termasuk arthropoda. Lumut menyediakan habitat mikro, tempat berlindung, dan sumber makanan. Penelitian ini bertujuan menganalisis struktur komunitas arthropoda pada lumut epifit di Kebun Raya Bogor (KRB). Prosedur penelitian yang dilakukan meliputi pengumpulan dan indentifikasi sampel lumut; pemisahan sampel arthropoda dari sampel lumut, serta identifikasi sampel arthropoda. Pengambilan sampel lumut dilakukan di tiga blok menggunakan metode plot kuadrat. Sampel arthropoda disortir dari sampel lumut di bawah mikroskop stereo, kemudian diidentifikasi berdasarkan buku identifikasi dan dihitung jumlah masing-masing morfospesies yang ditemukan. Data dianalisis untuk membandingkan struktur komunitas arthropoda antar blok berdasarkan indeks keanekaragaman (H’), indeks kemerataan (E’), indeks kekayaan jenis, dan indeks kelimpahan relatif (Di). Hasil penelitian diperoleh 21 jenis lumut dari 15 marga, dan 7 suku, serta dua jenis lumut lainnya belum teridentifikasi. Lumut dari suku Lejeuneaceae (9 jenis) paling banyak dijumpai di KRB. Sementara, artropoda yang ditemukan meliputi 36 morfospesies yang teridentifikasi sebagai anggota dari 3 kelas, 14 ordo, 15 sub ordo, dan 22 famili. Taksa yang dominan di ketiga blok adalah Liposcelididae, Formicidae dan Oribatida. Kelimpahan dan kekayaan arthropoda tertinggi ada pada Blok II (Lauraceae). Arthropoda yang ditemukan hidup pada lumut di KRB memiliki beragam peranan ekologi, meliputi herbivora, fungivore, detrivora, dan predator., Bryophytes play an important role for the life of bryofauna, including arthropods. They provide habitats, shelters, and food resources. This study aimed to analyze the structure of arthropod communities in epiphytic bryophytes in Bogor Botanical Garden (BBG). The research procedure includes the collection and identification of bryophyte samples; separation of arthropod samples, and identification of arthropod samples. The bryophyte sampling was carried out in three blocks using the quadratic plot method. Arthropod samples were sorted under the stereo microscope, and then identified based on identification books and counted the number of each morphospecies found. Data were analyzed to compare arthropod community structure between blocks based on diversity index (H'), evenness index (E'), species richness index, and relative abundance index (Di). The study obtained 21 species of bryophytes from 15 genera, 7 families, and two unidentified species. Bryophytes from the family Lejeuneaceae (9 species) are most commonly found in BBG. Meanwhile, arthropods include 36 morphospecies identified as member of 3 classes, 14 orders, 15 sub-order, and 22 family. The dominant taxa in all three blocks are Liposcelididae, Formicidae, and Oribatida. The highest abundance and richness of arthropods is in Block II (Lauraceae). Arthropods found living on bryophytes in BBG have a variety of ecological roles, including herbivores, fungivores, detrivores, and predators.
Keyword: arthropods, bryofauna, epiphytic mosses, community structure

Judul: Lumut Terestrial dan Ganggang Asosiasinya di Kebun Raya Bogor
Abstrak: Bogor Botanical Garden is an ex-situ conservation which may serve as habitat for bryophyte. Terrestrial bryophyte usually grow on various substrates in shaded habitat or open habitat, such as roadside, along ditches, and rivers. One of the bryophytes benefit in ecosystem is to provide microhabitat for algae. This research was carried out to inventory the bryophyte species grow on terrestrial substrate, and to study their diversity and algal association. The bryophyte were collected on various terrestrial substrates (soil, root, and rock). Quadrates of 25 × 25 cm² were used to sample bryophytes along 30 m transect on three blocks which is dominated by plants with different family, i.e. Meliaceae, Myrtaceae, and Lauraceae to study the diversity. Bryophyte were also sampled used sub-quadrates of 2,5 × 2,5 cm² in the quadrate of 25 × 25 cm² to sample algae associated with bryophyte. Forty three species of terrestrial bryophytes were identified, including 33 species of mosses and 10 species of liverworts. The bryophytes diversity was significantly different when compared to different blocks (p < 0,05). The highest diversity of bryophyte was on block Meliaceae which were more intensively shaded than on any other block. The bryophytes composition was different inter block. Fissidens crassinervis var. laxus, Isopterygium bancanum, and Taxiphyllum cf. taxirameum were dominated on three blocks in Bogor Botanical Garden. These three bryophytes species are commonly grow on soil and roots. Thirteen morphospecies of algae were found in association with terrestrial bryophyte, i.e. Cyanophyta, Chrysophyta, and Chlorophyta.
Keyword: 

Judul: Analisis dan Implementasi Certificate Authorities (CA) pada Public Switched Telephone Network (PSTN)
Abstrak: Secure Telephone Protocol has ability to authenticate involved party and keep the secrecy of the message sent over the protocol. The secrecy of the message archieved by using symmetric key cryptographic scheme, and authentication archieved using public key cryptographic scheme. One of several party involved in the protocol and hold an important function called Certificate Authorities or CA. CA responsible for generating public key pair for other party involved in the protocol. When CA generates public key pair, several primitive cryptographic scheme used for guarantee the security of the key. Two of them are hash function SHA-1 and El-Gamal public key scheme embedded in Digital Signature Algorithm scheme. The prototype implementing the scheme above developed using Java programming language with JCE addition from Bauncy Castle. The analysis towards implemented prototype indicates that the prototype still has some flaws to be implemented in real world.
Keyword: